A four stroke would be nice, that's for sure. The only 4 stroke I own is an OS .52...and that's not going to do it. In todays economy I cannot justify purchasing another engine for the Astro-Hog when I have two new engines sitting on the shelf. I am leaning towards the .55AX the more I consider the givens as I believe it will fly the plane nicely without the "overkill" aspect as you bring up, not to mention I can use a shorter prop on the nose, too. In my younger R/C days (daze ) I'd have gone for the "straight up" factor...now I go for the fly for the fun of it.

Joe