Nice system, the Prime is a very good table and arm combo, I also have one. The 20 Dynavectors are really good carts that I like better than there 17D series they just sounded better to my ears, with that said The Shelter 501 is the least expensive cart I could live with in my system after tasting some really nice carts and settling on the Dynavector DRT XV1s, XYZ Universe and a Mayabi Standard that I rotate in and out of my system. Do not discount the bump in performance when you add the perifial ring and a good screw down clamp, I use a BDR clamp. The last 2 Shelters I bought new, a 901 and a 501 I bought from 2juki on EBay great prices and a quality dealer. Also pick you up a mint best protracter to set that arm. Good luck would love to hear what you wind up with and how it helps with your JC3.