I'm wondering if it's possible to somehow use 16g C02 cartridges in conjunction with a counter pressure filler (or Beer Gun). The first problem is that the pressure cannot be regulated (unless you buy the expensive mini regulator from B3 along with the 72g cartridges). The second problem is...
I have a two vessel system and skip sparging. I cover my direct fired MLT with some towels and it maintains temperature within 1-2 degrees. My original system was more than 4x the cost of the system I use today. I've gone quite minimal with hardware and am much happier for it. YMMV.
I brewed with San Diego Super yeast in a double black IPA two weeks ago. It went from 1.088 down to 1.015 in less than 7 days at 64F (~83% apparent attenuation).