I haven't tried Xolox yet, but I think Gnucleus has the best resume of any gnutella peer I have used so far. Like you I could never get LimeWire to work reliably with this, but with Gnucleus, if you can find the file again, you can resume it. It's a very important feature to me since I share and download big files (about 120 meg on average). The chances of getting it all from one host in one session are usually slim.

Really I like the re-searching. For me trying the same IP often doesn't work. Often a host will go offline only to come back with a different IP address, and firewalled "pushable" hosts can't be connected to directly at all (yet they often have the fastest transfers if you can get to em').

One trick is Gnucleus lets you redefine the search terms before re-searching (right-click over the file name in the "partials" tab).

By default it uses the original search terms, but if they were overly broad (like "Divx" or "mp3"), you'll have trouble finding the file again. Instead try entering a key part of the filename - the results will be much better.