Most trainers will turn just fine on rudder , sans aileron . Most trianers have sufficient dihedral and work well . It is indeed easy enough to test beforehand .

I have used many trainers for many students with the ailerons disabled . In some cases it proved extremely helpful as a bridge and confidence builder . We had one instructor who basically forbade students from learning on 3 channel "blankety blank" trainers . He also had a few long time "students" that had tried for months but were unable to solo . I worked with a couple of them for less than a day and had both taking off and landing quite well .