Go with foam. The Shockflyer is a trusted favorite. It will do anything you ask of it. Here's the secret to cutting your expenses...Before you put the kit together, trace every part and make your own plans. The planes won't last forever, and who wants to dump another $40-$50 on a brand new kit? You can rebuild from your plans using Blue Cor foam or depron. You can even let friends borrow your plans and have a whole fleet of mimics.
Also, don't go nuts on the hardware. hobbycity.com has tons of low cost options for powering a foamy 3D plane. Check the Motor/ESC/Prop link for $15 combos that work great. Go for the Hextronik 9 gram servos. They're only $3.49 and I haven't broken one yet. Let's see, $15+(4)$3.49=$28.96+ about $5 for shipping. I think you'd be lucky to get the motor for that price from Tower or Hobby Lobby. Also, check out the LiPo selection. They're insanely cheap and they come with great warranties.
Sorry about the Hobbycity plug, but I'm tired of getting ripped off on RC parts by my LHS and most online retailers.