I'm looking into a used MXT 45 and had a couple of questions. I understand that the chassis is motorized. Is this unit still usable if the motor dies? How easy is it to align? One of the reasons I want a better enlarger is because my current one cannot be aligned (it's a student model) and I never can get sharp prints to the corners. Also, anything to be wary about with an Aristo cold light head? Any other thoughts from those that have used this setup? Thanks.