I just updated the post I made in this forum when I bought one a year ago also - but to recap.
I bought one on sale last fall for about $65 out the door (new from HF) and have used it for remote power when we tailgate for football games and also a few other events.
Last year I ran it an average of about 8 hours per game, for 7 games. Mix in some other events I used it at, and the break-in run time at home, and I have right in the ballpark of 100 hours on it. Probably a little more.
The whole time it's been running Shell 93 gas (might have had a little Marathon 93, but I think it has all been Shell) and Stihl HP Ultra at 50:1 (same gas/mix I run in my Stihl MS361 saw, Stihl trimmer, and Echo blower). Also been using an AL64 plug.
It does, and has always had, a little knock to it - but has worked fine in temps from 20F to 100F.
It sat from winter until last nigh in my garage, totally neglected. Fired right up and ran fine last night, but has developed a leak in the gas line. I'm going to pick up one today to replace it and it should be good-to-go for this weekend's game.