ho2zoo,

The kit has birch ply motor mounts that correctly give you 3 Degrees of right and down thrust. You could skip using these and re-inforce the firewall and use a standard motor mount but I think the profile of the kit would suffer because the engine would really stick out significantly.

The only issue I have ever heard about reliability with an inverted engine is storage as you don't want to store the aircraft with the head down after flight but other than that I think your good to go.

Marc