If you want a dedicated, space-saving stacking solution for two kayaks on almost any bar shape, choose Malone Stax Pro2; if you need a heavy-duty side-load system that doubles as a versatile multi-sport carrier for larger vehicles, choose Vallix 2.
• Malone Stax Pro2: Its biggest strength is the vertical stacking design that saves roof space and fits round bars; its trade-off is the complexity of loading two boats vertically compared to side-loading.
• Vallix 2: Its biggest strength is the robust J-bar side-load capacity and versatility for canoes and SUPs; its trade-off is the lack of compatibility with round crossbars and a heavier overall footprint.
• Who it's for: The Stax Pro2 is ideal for solo adventurers or couples who prioritize aerodynamics and roof clearance on track days, while the Vallix 2 suits families or groups needing a rugged, all-in-one setup for varied watercraft on SUVs and trucks.
The Malone Stax Pro2 is engineered for a very specific scenario: getting two kayaks onto your roof without sacrificing half your vehicle's width or fighting with wind resistance. This is not just a pair of separate racks bolted together; it is a unified stacking system designed to hold two boats in a vertical column. If you are heading out for a weekend of track days where every inch of aerodynamic efficiency counts, this system makes sense because it folds down completely when you aren't using it. That folding capability means you don't have to wrestle with bulky arms sticking up while driving back from the lake or heading to a race track.
The construction relies on octagonal aluminum posts paired with injection-molded nylon platforms. This combination provides a rigid structure that resists flexing, which is critical when you are securing a load high above your vehicle. The proprietary stacker blocks are a key feature here; they stabilize the boats during the tie-down process and cushion them against road vibrations. Unlike generic foam pads that might shift, these blocks are integrated into the design to keep your hulls tight and secure. The system also comes with universal fit JAWZ mounting hardware, meaning it adapts to round, square, and most factory oval crossbars without needing special adapters.
However, this product isn't for everyone. The vertical stacking method requires more effort to load than simply sliding a kayak onto a side-mount. You have to lift one boat onto the platform and then stack the second one on top. If you are carrying heavy, wide vessels, this might be physically demanding. Furthermore, while it works on most bars, it is specifically designed to maximize stability through its unique geometry rather than relying on the width of the rack itself. If you frequently haul canoes or paddleboards that are too wide or shaped differently than standard kayaks, this system might feel restrictive. It is best suited for those who primarily transport two identical or similar-sized kayaks and value a low-profile look when the gear is stowed.
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-11-06 · 6 min read · Independent comparison
The Vallix 2 takes a different approach by offering a complete four-piece set of J-bar carriers. Instead of stacking boats, this system holds them on their sides, utilizing a wide-mouth design that allows for quick loading and unloading. This is particularly appealing if you are transporting two kayaks simultaneously but prefer the ease of sliding them over the bars rather than lifting them into a tower. The set includes four units total, which provides the coverage needed for two boats across a wider span of your roof. It is built from heavy-duty alloy steel with a rust-resistant finish, suggesting it can handle the harsh conditions of saltwater beaches or mountain lakes without corroding quickly.
One of the standout features here is the versatility beyond just kayaks. The J-bars accommodate canoes, surfboards, and stand-up paddleboards (SUPs) up to 36 inches wide. The extra-thick, oversized foam padding protects the hulls from scratches and road noise, while the adjustable spacers ensure a snug fit for various widths. The package even includes four upgraded tie-down straps designed for high-speed highway stability, which addresses a common concern about loads shifting at speed. This makes it an excellent choice for families or groups who plan to take multiple types of watercraft on the same trip. The installation is marketed as a "no-headache" process with a bottom-flange thread design that should take about ten minutes to set up.
There are, however, significant limitations to consider before buying. The most critical restriction is that this system only fits square, oval, and flat crossbars; it will not work on round bars. If your vehicle has the classic round factory rails often found on older SUVs or certain crossovers, this product is immediately disqualified. While the alloy steel offers durability, it adds mass to your roofline. This is a robust, heavy-duty solution, but it demands a vehicle with the right bar shape and the physical space to accommodate a wider spread of equipment on the roof.
• Best for round crossbars → Malone Stax Pro2: The Vallix 2 explicitly excludes round bars, leaving the Stax Pro2 as the only viable option for vehicles with traditional round roof rails.
• Best for vertical space saving → Malone Stax Pro2: The stacking design keeps the profile narrow, whereas the Vallix 2 spreads out horizontally, requiring more lateral roof clearance.
• Best for multi-sport versatility → Vallix 2: If you plan to carry canoes or wide paddleboards alongside kayaks, the J-bar design handles these shapes better than the specialized kayak stacks.
• Best for quick side-loading → Vallix 2: Sliding a kayak onto a J-bar is generally faster and requires less lifting than stacking a second boat on top of the first.
• Best for high-speed highway stability → Vallix 2: The included upgraded tie-down straps and heavy-duty frame are specifically noted for maintaining stability at highway speeds.
• Best for compact storage → Malone Stax Pro2: The ability to fold the entire unit down makes it superior for drivers who want to minimize drag and clearance issues when the gear is not in use.
• Best for wide vehicle roofs → Vallix 2: The four-piece set covers a broader area, making it easier to balance loads on wider SUVs or truck beds.
For a buyer torn between these two options, I would personally buy the Malone Stax Pro2 if my primary goal was preparing for track days or frequent trips where aerodynamics and easy storage matter most. The ability to fold the rack down and its compatibility with almost any bar shape gives it a practical edge that the Vallix 2 cannot match. However, if you drive a vehicle with square bars and need to haul a mix of canoes and kayaks without worrying about vertical lifting, the Vallix 2 is the stronger, more rugged contender. In my opinion, the Malone system offers a smarter engineering solution for the average enthusiast who wants efficiency and reliability, while the Vallix system is a heavy-duty workhorse for those with specific bar requirements and diverse cargo needs.
It is not compatible with round bars, so you must check your vehicle's roof rails before purchasing.
The Malone Stax Pro2 is likely better for fuel economy because it folds down completely when not in use, reducing wind resistance. The Vallix 2 stays mounted on the roof and has a wider profile, which creates more drag.
No, the Vallix 2 set comes with four upgraded tie-down straps included in the package to secure your boats during transport. The Malone Stax Pro2 focuses on stabilization blocks rather than including straps in its core description.
The Malone Stax Pro2 features tool-free assembly and universal fit hardware, which suggests a straightforward setup process. The Vallix 2 claims a 10-minute installation time using a bottom-flange thread design, indicating both are user-friendly but require different mounting techniques.
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