I realize this is a support forum but I thought I'd post... At least for a while. I have a .58-CD in a trainer and it is a fantastic flier. It fits nicely and flies like a trainer should. Attached are a few pictures of the CD on an Arrow trainer.

I had an .60-SP in a Sig LT-40 for a while and it flew well but plan on making new landing gear. A good choice for a 2 blade prop would be a 16x12. That did NOT fit on my stock LT-40. Even with a 4 blade prop, you are looking at least 13" dia. I remove the .60-SP only because I ended up putting the trainer on floats and wanted a bigger motor (Profi .60 2-C).

Bill