Go here for a full review I wrote a couple of years ago: http://webpages.charter.net/rcfu/Kit...Extra300S.html.

I currently fly mine w/ a OS 120 Surpass, which gives excellent performance. A fellow club member has powered his w/ a ST 90 2-stroke with equally good results. A 1.08 size engine would be an excellent match IMO, but I have no direct experience w/ Magnum brand engines.

Have fun - you're going to love this plane!