I've bought tubes here and had great service. Even had 2 go bad 6 months later and he replaced them free. Wasn't his fault and he really took care of me. I have 2 friends and between the 3 of us I've bet we've bought 2-3k worth of tubes from BWS. We've all been happy...
http://www.bws-tube.com/
http://www.bws-tube.com/