Hi,
Here's my observation have two friends that run the CMB 45 VAC with the CMB straight nitro pipes, they make awesome power, and rpms...both are on riggers.
Also had the pleasure to see Jason Brown's 45 Eagle fitted with the new 46 Nova at the fall Nats this month and although they are still in the fine tuning stages, also made amazing power and rpms to the moon!
As far as breaking parts, that is all relative and depends alot on proper set up, care, and maintenance.
Like with most engines to obtain optimum performance they could almost always benefit from minor tweeks and mods, but with these two in particular it does'nt take much.
Definately, two very!! stout!!..motors,..that I'll be keeping a close eye on!
Happy Boating,
Elias