Rafa,

the Hobbico 10 sized mains are nice. They use 3/32" struts so are intended for 10-15 sized models including 1/2A. For the 20-30 sized models we want 1/8" struts and a stronger retract body much like the Robart's, MK's and Spring-Air 600's discussed above.

I have no experience with those servo's but they sound good. Anything with the torque equivalent of an HS-65 should be fine on the Hobbico 10's.

Since you already have a Picorare (Tipo 15), the Magic 20 sounds like a nice project. I wouldn't let some retracts or servo's affect your building plans! I'm basically building the D15 as building practice with foam wings and mechanical retract installation. A larger model would have been easier though. I'd venture the cost difference between a 15 and 30 size model is about 20%.

Having said that, the D15 is a fun model to build. Simple design, clean lines and straight forward build. I was actually hoping to find a Webra .12 RE engine for it which were designed for ducted fans. I could have put a pipe on it running under the canopy! I'm not sure that I'll use a pipe on it now though as I have complete ST G20's with muffler and a K&B 18 with muffler.

We'll see.

David.