I have been happy with most disc golf suppliers that I have bought from.
My real opinion is that it really does not make a difference.
Hero Disc USA for Japan open discs.
Disc Golf Center for one or two discs or specific disks.
Marshall Street and Clearwater both require 50 and 40 of purchase for free shipping.
gotta go gotta throw is also nice. reasonable shipping
I have bought from all of these places. I have found all of them to be good for customer service.
Dynamic Discs, the best disc golf site in the world. They're a little more expensive than other sites, but they gave great dyes and stamps. Also fast shipping, they do a great job in promoting the sport. Let me know if you need something particular.
I like DiscGolfFlyMart.com....over 500 unique Fly Dye Discs to choose from... $3.00 shipping...good selection of production plastic...same day shipping...and oh yeah...I own it...check it out!! Only place to get all the 2010 Worlds CFR plastic.