First off there is a major probem on the Super Tigers that no one has mentioed. The carb barrel has a rough finish that will grab and lock the throttle in one position. This happens with out warning and can happen before the engine has even run 5 tanks of fuel through it. This problem is apparent in the smaller ST engines as well. Not to mention what a pain they are to try to get a relaible run out of them. The "you get what you pay for" doesn't always apply. I have one of the pricy OS 61FX engines and while it runs smooth and reliable, the power is disappointing and only mediocre. The best all around engine I found in the 61/75 range is the Tower Hobbies 75. You get "much More!" than you pay for. The engine is as easy to adjust for smooth running and a low idle as an OS but the engine has scary amounts of power. The muffler that comes with it is noisy but if you are going to put the Pitts on it any way then it shouldn't be a problem. At $95.00 the engine seems too cheap to be a good engine but, it is, a very good engine! I run one in my Stuka 60 because I wanted power and reliability and with this engine I got both.