External hard drive for expanding iTunes library?

My hard drive is nearly full and I need to get an external HD for my rapidly expanding music library. I use iTunes and stream the music to my Airport Express to my Marantz SR-7200's DAC . Using a bel-canto eVo 6 and Gallo Ref 3's makes good music to me. All my music files are Aiff(uncompressed) and currently use 106GB. I've read good reviews online about the G-DRIVE 500GB External Hard Drive but I'm curious if any other Audiogoners have used it or could recommend other large,quiet and reliable external hard drives. My computer is an iMac G-5.
Thanks for any help.
Howell