I'm a newbie so forgive me if this is a really vague question.

I'm wanting to know what generally is the most powerful engine brand of the same size EXAMPLE: an O.S. .45 compared to an MDS .45. I don't even know if these engines exist.
I'm aware that there are different models within a certain size of the same manufacturer i.e. LA and FX in OS models; consider the best one. I really hope ya'll are understanding what I'm saying. LOL.

Power is my concern, but I would also like to know if there are "MAJOR" considerations I should take such as very very short engine life (maybe due to all the power), unreliability (stopping in mid-air), and LESS importantly, ease of difficulty of use/tuning and price.

List the brands from most powerful to least.

Thanks in advance.