So, to summarize, 46 versus 55, half the folks say "no way...way over kill" and half say "good idea"...never knew the question would get such different opinions.

Regarding Greybeard's comments, the OS55 is only $30 more than the OS46 and essentially the same weight (+1 oz) so I tend to agree if I go with OS.

If I go for .46, how would you compare Towerhobbies 46 to ThunderTiger Pro .46? (at the risk of an equally split debate as they are the same price).

Seems it is becoming more a "lower cost engine" versus "top of the line" question versus SIZE...do I go for less than $100 engine (and hence 46) or >$100 in which case OS55 wins? Am I thinking about this right?

Of course, you could say the same thing about the plane...4* versus Dolphin to save $50.

What prop for the 55? 46 seems 11x6 is suggested but I have read many people using 11x6 on the 55 too. With the same prop, what would the difference really be? Just torque? RPM higher on the 55?

You can tell I am not sure where to spend the money and whether I "future" proof the engine or go quality on plane which might get crunched.

(Maybe I'll move the TH 46 over from the trainer and try that out to start...)