MAX6 SVNA is improved version of MAX4 VNA, improvements are :

extended bandwidth: 0.1...180MHz, increased output power level: more than +15dBm, extended dynamic range of Input: -60dBm...+20dBm typicaly, SD card for records of the measurements, IR Remote Control for easy and fast access to all functions, Synthesized Voice transmited for example at 145.225MHz AM/FM, so you can listen whats going on with your portable while you make changes to the antenna, Firmware can be upgraded via USB. As MAX4 it can be used as wobbuloscope also. Many other things that you can do with it can be found on webpages of Jarek - SP3SWJ:

if polish is incomprehensible for you, please use translate.google.com

https://sites.google.com/site/max6notatki/home 

http://sp3swj.googlepages.com/

When i bought mine MAX6, mini kit for MAX6 was not available and MAX6 was sold as a completely finished assembled working device, as on picture with IR Remote, case, charger, SD card & SD card reader. From 18.02.2009 MINI KIT MAX6 is available also.