tonywayne, I'm not suggesting you're one of these people, but some - IMHO - tend to get too serious about stuff like this.

I own both, and for me it is strictly a matter of character. Some designs just look, sound and fly better with 4-strokes - again, my opinion - like a Cub for example. Other planes seem to look and sound absurd with 4-strokes, like a Curare, for example.

Sandyt is discussing performance which is also important to consider (I know, it's everything to a lot of people).

I would recommend you buy one and give it a try. You will see what I mean about how they have a character all their own. And that might lead you to build some new designs that you've may have overlooked in the past.