I've had the best luck with SF.com, probably 100x SFP's of varying speeds distances and connect options over the years never had a failure etc., always seemed to have the cheapest copper SFP's too for 1 and 10gbps options.I'm a big fan of 10GTek modules. Typically very solid for a reasonable price. They also go on sale a lot.
You won't be disappointed. We've set up several of them for clients and they're excellent performers.

