The Dyna started in 1993 or so, before that its predecessor was the FXR, which by most accounts was a better handling and riding bike. Disclaimer: I ride an FXRS-SP. If you can find an FXR from 88 through 93, it will cost much less than a Dyna, and once you're over 2,000 RPM's hardly vibrates at all. The FXR uses a three point rubber mounting system, the Dyna is only two, which caused some problems on the early to mid 90's bikes, something about cracking the transmission?I just got back for demo days and was half impresed I think I am in love with a dyna super glide but I know I can aford one. Maybe a late 80 or early 90 how much have the changed? I have also disided that the newer sporster vibrat a lot the seat is uncoftable and on the 1200low the handale bars sucked. I wached a 03 sitting right next to a 08 the 08 had biger side to side shake and 03 had a all arond viberation. The power from the EFI did impress me but I had a hard time telling what gear I was in and went to shift Inexsperins I guess. I did how ever but to rest the thought of getting a 883.
The Dyna came with the Evo motor through 1998 or 1999, and the twinkie after that.
My personal recomendation, go with an FXR, you'll love the ride, and the Evo motor is easier to work on.