Virtually all of the standard 40-size trainers will do the job -- you pretty much can't lose, regardless of which trainer you choose. The RTF packages are great if you are a bit thin on time, or building skills -- they also come with acceptable engines and radios. ARFs are a bit cheaper, but you have to outfit them yourself & you will be confused by the very wide range of opinions that you will get here. Your local hobby shop will almost certainly give you good advice & possibly some physical help as well.

Have fun.