DIR-655 A3, Using COMCAST Business Gateway with static IP, Running several web servers, I would say above average traffic. My story:
Upgraded from 1.21 to 1.32NA. Started to have router lockups every 2-3 days. Even with DNS relay turned off. The firmware was running slow, some pages were loading noticeably slower than 1.21. I don't use sharepoint (therefore cannot validate this feature).
Installed 1.32b09NA 7 days 11 Hrs ago, running no problem since then, with DNS relay now turned on. And firmware seems to be loading pages quickly. Finally!