There is no concensus, everyone just posts the propaganda for his favourite client. But as far as i know most users prefere either BearShare (Windows only) or LimeWire (Cross Platform). Another famous one is ToadNode, but i never got it to run without crashing my system. BearShare will install SpyWare on your system without explicitely telling you about it, and LimeWire, written in Java, needs a lot of system resources. I would recommend LimeWire anyway, because it should run without any bigger problems on every modern system and - warning, personal opinion - returns the most search results and is faster than any other client.