I got my SA20 with a 12" diameter bit a month ago and have used it a couple of times just for testing to get the feel for it. On the 2601, it gets a little "tense" on slopes when it's lifted up to get it lined up, but lowering the BB helped a bit. Once started, it easily went through clay and small roots. I even used it at a 30-dgree angle to help break up the soil in out a 1' wide trench. Not what it's intended for, but it worked well once it got it at an angle where the bit didn't bounce.
Mine came with one male and one female hose end which meant I couldn't use it until I replaced the male connector. Not sure if that was from LP or from my dealer.
What else would you like to know?