except what if you got the superstar .40 and a tt .46? cheaper. bigger is more expensive inherently than getting the smaller but same grade equipment. honestly though, in a trainer, all .40 trainers are pretty stable. the only difference is they respond quicker than the larger ones. it would say that because the benifits are minimal in regards to going bigger on a trainer, go with the smaller one. it's cheaper. some people prefer the larger size planes. myself included. but trainerwise, they both do as good of a job.your question is bigger or cheaper. it's a matter of preferance.