There have been several discussions regarding the Aeron on this forum. You should do a search on this forum and you'll find numerous postings on the Aeron that may be helpful to you. Pending on its current state of construction, there a couple of mods that you can do:
1. Cut out lightening holes in the front two 1/8" lite ply doublers, though make sure that you leave enough material in the right spots for the mounting of your fuel tank.
2. Omit the cross braces in the control surfaces - I've done this sucessfully on others.
3. Hand pick the bottom 3/8" SQ. Balsa piece to be medium density balsa that runs along the bottom of the fuse in the rear of the fuse. Then you can omit the 1/16" fuse sheeting. You can also install a CF rod in the fuse to add ridgidity to the fuse without adding alot of weight with confidence when you omit the fuse sheeting.

Engine - either one will do just fine. The Aeron is designed for a 32 to 50.

You'll find the Aeron to be very algile and quick, capable of aerobatics that don't have a name yet - -

You'll find some movies of mine flying on my website along with some construction pics. DKJens just finished one, and Paul Swany is finishing one up. You'll find both post on this forum.
Let me know if you have any questions once you get it, and let us know in what state of construction.
Kevin