For me, SD is too much a PITA to keep swapping out. I'm waiting to hear of success using SDHC cards, then I might buy a 16gb card and let it run.
For wireless, I tried Firefox (IE didn't work at all), but it would only run for a 1gb or so before is stalled. Then I tried WGET, which is a GNU freeware program that runs from the command line. It also bombed out around a 1gb or so, but it features a resume feature. It worked for one disc, but for another, it wouldn't resume properly after it timed out.
I believe the problem is with my wireless setup. I keep thinking it's my router, but rebooting the router doesn't fix anything, only rebooting the Wii and resuming the transfer works.
For me, I currently use Wiiftp to mount the DVD (I think only the lastest version can do this, 0.0.16). Then I use Filezilla (or use your fav ftp program) do download the file. It still bombs out a couple times per disc, but at least I've never had a problem resuming the download. Takes about 2.5 to 3 hours. So far, I've done at least one dump with each method, never a single problem with the iso. Oh yeah, I almost forgot, if you use Wiiftp, the img file is the same as an iso, or at least I think so. I just renamed it to .iso and ran the IOS patch against it to drop it down to IOS level 30. If anyone has any better ideas, I'm open for suggestions.
I'm going to try the USB to Ethernet adapter solution tonight. It's a cheap $8.00 converter I bought off ebay a while back, so I'm not holding my breath, but it's promising that others have had some luck with them.
Someday, I'll find a damn LG 816x dvd rom drive, but everyone is sold out, big surprise there, right?