I've talked to Maverick and we will get my parents-in-law a WAG310 directly from WxC. It seems the problems with DLink are well known - they can't handle changing IP and forwarding the ports to PAP boxes very well...
I'm running the WRT54GL as my home router running the Tomato Firmware (http://www.polarcloud.com/tomato) - and it's awesome.
Would recommend it to anyone.
...although of course you'll need a separate modem - draytek vigor 120, TP-link 8810 or dynalink RTA-1320 (beware its cheap overheating capacitors) will all do nicely. You'll also need an ATA adaptor - PAP2T or SPA2102.
Received the WAG310 last week, installed on Friday. On the first configuration attempt LINE2 was locked out, so called WxC on Sunday to ask to unlock it (parents-in-law have mynefone on LINE2).
The help desk logged a request for a new config file but said it wouldn't be before Monday because someone else had to do it. No problem there, the old PAP2T was still working for mynetfone. But half an hour later I got a call back on my mobile and the help desk said they had created a new config after talking to someone, and after loading the new profile it was all go.
Only a couple of days with the new router, but I am hopeful.