Rigger1,
The Grob Tutors definitely do not have glass cockpits! We get a good return from them as all elementary pilot training is carried out on them. They do not just belong to the UASs - all RAF trainee pilots fly them before going on to rotary / multi / fast jet training.
As for the cost, well, they're owned by RBS - so we haven't laid down a pile of cash. Not sure what the annual "rent" works out at, but it's not going to be a huge sum in terms of potential savings...