The Epson Workforce seems to work okay over Shareport with the DIR-655 router (even the scanner), but it is very flakey and intermittent. Re-booting the router seems to always fix the problem. Also, The drivers from Epson DO NOT work over shareport in Windows 7 64-bit, but the default Microsoft driver will (go figure).
So, regarding the DNS-323 -- what I am hearing is if I want to use it as a print server with my existing printer, it'll work, but I have to use Sharepoint and it will probably be no better (or, hopefully, worse) than what I have come to expect from the DIR-655 router. Disappointing they haven't improved upon that but it is what it is and not really a reason to put me off not buying the DNS-323 (still thinking about it).
Also, good suggestion about resetting the router to DEFAULT settings, saving, rebooting and resetting all settings manually. I haven't tried that but I will (and I am running firmware v1.34 on the router).