IMHO
All around awesome speed, prices, quality and is SAFE (domestic): GP
Best prices, quality and variety, but a could be a wait and risk of seizure: Alin
Look at some of the ones with the polls. That will tell you how most feel about the dealings with those sources. One thing nice about this board - if there are complaints - they will not be here long - ask chevin
I have used a number of them and I honestly couldn't recommend one as better as far as quality goes.
You do tend to develop a relationship with sources you use more often.
it is always good to spend time on the message board and read through the responses from people who have ordered from the sources listed. this will give you an idea of which ones tend to provide better service which is just as important as the pricing of products they sell. there are 3-4 listed here that consistantly get great reviews from their customers.