Wireless network connection lost frequently...

I have several machines, 2 Windows notebooks, a Mac, and another Windows
desktop running XP, that all keep their network connection perfectly. The
only machine that drops the connection constantly is the one running Vista.
I'm using a Linksys WUSB54GS wireless card and a Linksys WRT54GX router, and
this equipment worked fine under XP. The computer itself is more than
sufficient to run Vista.

Does anyone know why this problem continues? Any suggestions on how to solve
it? Please don't tell me to go back to XP, I paid way too much for Vista to
not use it.

Now, a bit of a rant...why the heck, in the months of beta testing, were
problems like this not solved? I have to say that Vista seems very much like
a still-in-progress beta, rather than a commercial product. When is this OS
going to start coming together?

Sorry, but I am just frustrated with the continuing problems with Vista. I
feel like I'm part of some unsolicited testing group.