The TT should be fine. As far as retracts or fixed gear- I for one am happy with the fixed gear trend as retracts were always a PIA for me, but our home field was fairly rough grass.
The MK retracts are the best, you can get them from Central Hobbies or Gator RC, probably other places as well.

I see you're in Rome, come on down to our area in August for the Aeroguidance Society pattern meet!

Scott