I don't have one of all the above brands of engines (and I doubt that many respondants do) so this poll is probably not a lot of use.

However, I do have a TT46Pro that's done over 300 hours and is only 200RPMs down on a brand-new one.

I've also seen a TT46Pro lose a bearing retainer and spit out a couple of balls from the rear bearing (they must have gone up the transfer ports and out the exhaust because when we took the backplate off they were *missing*) and that engine is still running as good today as a new one. Fragments of the retainer put a couple of *very* small scratches on the piston and dents in the head but a few runs on hi-castor fuel with a very lean needle and the compression came right back up to "as new" levels.

Of the dozen or so TT46Pros in our club, not one has had to be retired yet -- which is more than can be said for the likes of GMS, TS, ASP and a raft of other Chinese brands.

Our club trainer also has a TT42GP that spends as much time burried in the ground as it does flying through the air but, after four years of near-constant use and abuse, it's still going really strong and remains 100% reliable.

We've lost one SuperTigre 90 to piston failure (it fell in half) but the other 3-4 in the club seem to be going just fine.

Two OS46FX engines have been retired well before their time due to peeled liners but the AXs seem to be holding up okay, although they do lose power as they get older, while the TTs are still pulling strong as new.

We've lost a GMS32 due to being just plain "worn out" after no more than 10-15 hours. It was used with a tuned pipe however and may have had a lean run or two. Others have retired their GMS47s because they're just too damned tempremental when compared to the TTs.

It's interesting to note that, after at least 10 gals of fuel, my TT61GP is still so tight (ABC pinch) that an electric starter won't turn it over in winter when it's cold. By comparison, my ASP52s were also *very* tight when brand new but after less than a gallon of fuel they've lost all their pinch (but still run well).

Most modern engines are pretty damned good but if I had to choose I'd say Thunder Tiger for 2-strokes and Saitos for 4-strokes.