I've been a Summit user for the last 4 years. I bought a Cobra X4 when they redesigned them and put the climbing stirrups on them. Very solid, stable and comfortable stand.
I just picked up a 2008 Lone Wolf Sit and Climb (actually, I won it through a gun raffle
) I gotta say, I wish I would have owned one before. They're more packable, easier to carry and with the new 2008 seat, almost as comfortable as my Summit. The selling point with the LW is how quiet they are to use. They don't make a sound other than from you scraping the tree with the back of the platform as you raise it.
I absolutely love this stand. Its now my primary climber. I haven't taken the Summit out since.