It doesn't choke on a few hundred gig of files, doesn't want to sell me anything, doesn't want to show lyrics, doesn't try to do anything except let me search for songs and play them.
I use Goggles Music Manager.
I also like Quod Libet.
I've got about 46,000 songs and neither slows down or hiccups at all on my collection. (All stored on an external usb drive)