More daunting then continuing to find issue after issue with Vista, having to dig deeper into the unknown when things aren't working compared to the way they used to on the older Windows? Yes, I'm admittedly a big OS X guy now, but I still have to deal with Windows on a frequent basis at home and work.

I finally got tired of trying to live with Vista (After trying really hard for nearly a year) when:

1. Network performance sucked, and continued to suck post SP1, with new drivers, and on completely different hardware. Much like your issue, it was very noticible, and vanished when going to XP on the same hardware. The auto-tuning being turned off helped, but never got network speeds to what XP could do.

2. Sound drivers are still a mess. Even post SP1 and nearly 18 months after Vista went gold, I couldn't route the line in sound to the speakers on my desktop at work (how I listen to the empeg). Going back to XP worked, after trying endless combinations of various registry hacks and driver versions.

3. Buggy display drivers that bluescreen the box at the drop of a hat. This has gotten much better since NVidia and Microsoft got their acts together and released a few hotfixes and new drivers. However, something is still clearly borked when Aero is allowed to eat 2.9 gigs of RAM.

4. Unexplained differences in basic things like file permissions over a network, leading to a folder I can delete off the NAS on XP, but not on Vista.

5. Changes to how the screen lock works, to cause it to take a really long time to unlock a workstation under heavy load.

6. Slower disk performance on the same hardware as XP. Again bad enough to notice.

7. Worthless and problematic file and registry virtualization tied to a completely unrelated and worthless security system built to annoy users. Sure, I turned UAC off as a first step to get around being annoyed while not being provided any real security, so it worked around the bugs in the virtualization stuff.

All of this discovered by trying to use Vista as a primary windows box, but secondary work machine. I cringe to think the other issues I would have had if I depended on it for e-mail, word processing and other tasks as well above and beyond the development work I do on the machine. Not all of it might be a direct problem caused by Vista, however I see it as a problem MS needs to help address if driver writers can't get the same functionality and stability out of the same hardware due to MS rewriting so many core services with no noticeable benefit.

As far as I'm concerned, if a migration path to OS X isn't possible (and it is very easy with VMWare and such), and staying in Windows hell is required, at least stick to XP long enough to see Windows 7 make it out. The problems in Vista clearly cannot be addressed by the service pack team at Microsoft, so maybe the core OS team will fix the issues in the next paid version. Similar to how the service pack team couldn't fix the death star sized security holes in XP (MS had the core OS team work on SP2, hence one of the many reasons for Vista's delay, and possible problems), I don't trust them to fix serious Vista issues either, since SP1 didn't do much for the 7 issues above.