Unless you're into competition a .91 2-stroke will do just fine in that Venus ll. I saw a review video with a guy flying a .61FX 2 stroke in it and it flew just fine!

After all, it only requires a .61 - .91 2 stroke.

The review was from rcgroups but here it is....

http://www.rcgroups.com/forums/showthread.php?t=544852