I know this thread hasn't been active for a few months, but here's my two cents on the wifi issues I have experienced with the SB touch; First the touch will show you network and wifi status, including signal strength and a data integrity graph that can be set to specific KBPS rates so you can easily see if your network throughput is sufficient for the files you are playing. In my experience playing WMA lossless over wireless G, the only time I see buffering dropouts is when there are multiple users on the network doing high data rate downloads, even doing an internet speed test while playing music won't cause buffering if those two operations are the only network traffic. My issue with the SB touch has nothing to do with playback or sound quality, rather I have problems with the SB connecting to my computer after the computer has gone into sleep mode...if I try to connect (play music from the library) while the computer is asleep the network (SB server network, not the work group) fails, requiring a reset of the SB touch to reacquire the connection about 60% of the time. It also occasionally (10% maybe) fails to reacquire the network even if the computer is up and running before the attempt, but had been asleep since the last SB playback.
My solution is that I'm going to use an external USB hard drive to hold my music library, obviating the need to stream the data, it will eliminate the network issues (*never* have problems with Internet radio connectivity), and gives me another backup of the music to boot! It won't even be very costly as a decent external 1TB drive is under $100 these days.