I have bought some stuff there and gotten some good deals on the stuff that I needed. Keep in mind that the sales usually last no more than 2 days, so you have to keep on your toes with it.
There's a perpetual $10 off coupon. 10off, I think? You can save up credits ($5 every birthday, if you haven't purchased, etc). I got a Bushnell TRS-25 for $58 with credit and the coupon, which took care of the shipping.
I've purchased a couple items (at the best price I'd ever seen) with no problems....it is annoying that you have to wait for an item to go on sale but on the other hand that has saved me $$.
The 10off coupon does works on dvor, but only once. I've also gotten coupons included for their other sites but the prices are higher there!