While many people get good results in home ovens, especially those that heat up to 550, and many have had success with a steel plate in a home oven instead of a pizza stone, many users want more. Here is a link to a video of the BS in action by Jleonard711 Jleonard711 video
HIGH HEAT
In general, high heat is a good thing when making pizza. While 1000 degrees isn't needed, many types of pizza taste better when cooked quickly at temperatures in the 600 to 800 range. A home oven just won't give that temperature. The BS is powered by a propane gas burner that puts out tons of heat, and can easily hit 800 F, and go beyond it.
ROTATING STONE
Without a rotating stone, most ovens require that you turn the pizza from time to time, otherwise, the part further from the oven door will brown more quickly than the part closest to the door, since each time you open the door, you let out warm air, and let in hot air. Also, many ovens have hot spots which also would require you to move the pizza around while cooking to make sure it cooks evenly.
HIGH POWER
In addition to high heat, the BS has a 60,000 btu propane burner, which is a ton of power. No only will it get hotter that a home oven, it does so very quickly. It is not unusual to read that users preheat a pizza stone in their oven for 45 minutes to an hours. The BS gets the pizza stone up to temp in 10 to 15 minutes. If you are only going to make one pizza per session and can deal with slower preheat times, there are a number of 120 volt ovens sold in the US that will go over 550 degrees. Unfortunately, since they are usually limited to 15 amps, which is the same power as a hair dryer, it can take a long time to preheat - and hour to and hour and a half depending on the thickness of your stone, and the size of the chamber. The main difference that power brings is that when I used a 15 amp oven, I could get it to 580 degrees, but by the time the first pie had cooked, the stone temperature had dropped, and it would take a half hour to get back up to temp.
HEAT FROM ABOVE AND BELOW
One key to making a good pizza is to have heat from below and above, and ideally a way to balance the heat from those two directions. While many commercial style electric ovens have two elements with separate controls, most home ovens don't work that easily. Instead, you turn on the bake or convection element until the pizza stone or pizza steel hits a certain temp, then turn on the broiler element to get some top heat. This method can work, but with the BS, it is so much easier. Part of the flame heats the underside of the stone, and part goes around it, heating the cooking chamber, and heating an upper stone, which in turn radiates heat back down to the top of the pie.
The BS is not ideal, because you can't really balance top to bottom heat all that much during a cook, but there are ways you can adjust that balance before you turn it on, and one you have it balanced to your personal preference, you probably won't need to rebalance it. Adjusting Height of Lower Stone
In sum, the BS has some major advances over other options, especially if you want the ability to make more than one pie per session.
For those in Europe, you have some great options in electric ovens . P134H and GGF Micro Compared
In the US, there are not many high powered electric models, unless you go to 240 volts, which means a dedicated power line, or go to a small, 12 inch or less pizza.
For gas options, one extremely well reviewed option is the Pizza Party. Pizza Party Home Page. While it is considerably more than the BS, and originally was only wood fired, it is now offered in a convertible mode that allows the user to use either gas or wood fire, and it gets extremely high marks from users, both on its operation, and on customer support from its owner, who is a regular poster on Pizzamaking.com.
For a more portable option, there are a number of sellers that market a small gas oven, the stone does not rotate, and there are some issues at how it deals in the wind, but it is certainly a good idea for those that go camping, or don't want to put another grill in the backyard. Pizza Pronto at Sur La Table
Another option is a cover that goes on a separate heat source, such as Mighty Pizza Oven Mighty Pizza Oven