I wouldn't put a Saito 100 on a Mojo 40 -- the damned thing would be shaken apart within minutes. Even my Mojo60 gets severely battered by the vibes from my 100.

Remember that one of the key factors with any 3D ship is weight. I'd rather have a light Mojo with good power than a heavy one with outrageous power. Remember that lots of 3D maneuvers are done at far less than full throttle -- so then all you've got is a heavier (than normal) bird that won't fly as well as a light one.

And don't worry about the TT46Pro working too hard. I've had one in my Katana P (which, thanks to many repairs over the past 3 years) has gone from 4.25lbs to almost 5lbs. The TT46Pro still hauls that baby around really nice and since I switched to using oil from Cooper Fuels, I'm getting just over 13,000 RPMs on an APC 12x4 prop using just 5% nitro and a tower muffler -- that's *more* than enough power for great 3D and a lot of fun. I was getting just 12,500 when using Coolpower castor/synth blend with 5% nitro and even that was *heaps*.