I've only ordered from seedsman, twice, though I never grown any so can't speak on the quality of the products,. However, the seeds I received looks prestine. Also their promotional deals are usually unbeatable with lots of freebies if you combine with bitcoins, first order and holiday promos. Last order I got more free seeds than I originally ordered.
Now to the sad part. I'm not sure if I've had the worst of luck or whatnot, but the costumer support has been atrocious, lots of hassle and unanswered support tickets.
For now I'm stacked on seeds and looking forward to my first grow. Wherever you choose to order from I wish you good luck!