I'd go with cjd a320 and buy the CRP5, Just the larger size makes it easier to use and understand. Do get some lessons, most schools have a huge one for demonstrations, but younger instructors, who haven't used old technology at schools seem to struggle to teach it properly. Get the oldest, greyest instructor at the school to help you.
Many people deride it, I've used it for 30 years and have yet to find a really good electronic version.
I keep one in my aeroplane and one in my briefcase for doing gross error checks on what the FMS in the day job "office" says.
SND