I asked the same question the other day and sent to peakseedsbc.com yesterday. I'll post how it went. I don't know how to post the link here, look for old new guy needs help, there were some very helpful replies.
many use them, they have quite a wide variety of prices - you'll find there will be some complaints against all seed banks, but SB is 2 for 2 for me this year
MJ at PEAKSEEDSBC.COM totally RIPPED ME OFF and he is so being a dick about it. I mailed my order in the beginning of Oct 2009. I emailed him 3 weeks later and he said he mailed my order which I never received. He said he would resend another order. Never received it. Emailed it again and he said 'it must have gotten lost in the mail.' I emailed him 3 weeks ago and again he told me it must have a got lost in the mail. This time I told him that it was impossible for 3 orders to get lost in the mail and I wasn't buying his story. Now he will not respond to me at all. I did write to Greenman since now pekseedsbc.com has a Greenman symbol on his home page. It doesn't appear that Greenman is that honest either since he wouldn't do anything about him ripping me off. Also I searched the web and found many, many other complaints from people saying they never got their orders either. He may have been honest long ago and DO NOT BUY FROM HIM AGAIN.
Nirvana Seeds I always get my orders and one time i got a bad batch. Not one seeds germinated, and I let Nirvana know about it and they resent my order. Nirvana Is the only place I will shop for now.