as a CFI with too many thousands of hours of instructing from C152s to CRJ200s, and as a line pilot, take it from me. Learn in a traditional cockpit (6pack). Its cheaper, you'll learn better instrument scanning skills, and the transition is easier from round to glass. I have taught a LOT of people and every last one of them had an easy time going from round to glass. But the reversed ones (ones who learned in a Diamond and then went to the King Air....it was just rough.
A lot of people say "oh learn on glass because you'll fly jets with them one day". Well, my best advice is to fly the plane you are flying "now". No need to fly a little 1700lb Cessna 172 like a jet. Its not a jet. Fly the Cessna like a Cessna. There will be plenty of time to take the fun out of flying in jets later in your career.