Just something else to consider is the abuse that any trainer can be subjected to - tip stalls, hard landings, cartwheels, etc. While most of the traditional trainers are made of balsa. Being made of balsa, they tend to be a bit on the delicate side and do not handle abuse very well.
If you can follow some pretty simple instructions, take a look at
this SPAD . It's made out of corrigated plastic as are 99.999% of all SPAD's and they are tough as nails. The nice thing about SPAD's is the inexpensive cost of the materials.
I fly SPAD's and have retired all of my balsa planes simply because I like being able to crank out a new model each week if I so choose. I also like the fact that if I destroy one of my SPAD's, I'm only out about $20 and I can swallow that alot easier than I can $125 for a balsa ARF or months building a $70 kit.
It's just something to think about . . .