Bearshare is loaded with spyware, so I avoid it.

I've been using Limewire for a few months, and I like it's ability to be tweaked fairly well. Now, they've gone with ad banners

Xolox has turned out to be a very good client, although you can't tweak it like Limewire. Xolox will attempt to download a given file from multiple hosts, so your effective download speed amounts to the sum of each individual parallel download. Xolox is really aimed at high-bandwidth connections; modem users probably won't benefit much from the parallel connectivity.

I've tried others (Gnucleus, Phex, and Gnotella), but they seem to lack the ease I find with Limewire and Xolox. In a perfect world I'd really rather like to spend more time with each one, but my work and personal life kind of limit my gnutella phreaking.

Hope this helps, cheers!