I've heard a lot of good things about the TH .75, but I had a TH .46 that NEVER ran right. In fact, I've NEVER seen a Tower Hobbies engine run right. Just remember that if it sounds too good to be true, it is....you get what you pay for....and a whole slew of other cliches. I've NEVER seen anyone really have a problem with OS engines, but have seen nothing but problems on those Tower Hobbies engines.