Tough question. I would say that you have to shoot the proper weight broadhead that shoots straight with your setup. Having perfect arrow flight is what you are looking for whether you are using a 125 grain or 300 grain.

On the second part, again, it depends. I would think that a vented head will plane more then a solid head, doesn't matter if it is two or three blades. IN either case, once again, the arrow needs to fly straight. But a non-vented head will be quieter.

Personally, I'll take the non-vented two blade head with a single bevel.