This would be my experience exactly, not one single problem since I purchased it. I have a Linksys Wireless Router and a Wireless Access Point depending on where in my house I am, it connects perfectly to each one of those and downloads my refreshes. I have just for the heck of it connected via USB, but I much prefer Wifi myself.
I do think many times these issues are related to router configurations and much like the Sirius SL100 and SL2 any little thing out of the ordinary will cause them not to connect or to connect and then not be able to get internet access once they do.
By the way I talked with both my G1 gift persons just last night at a New Years Party and they have reported no problems and both are having great experiences with their G1 so those are not problematic for everyone either as some of the Slacker Forum threads would indicate.