I have bought from them a couple times. Never had an issue. I have only bought coins from them once, some silver Ikes below melt, but for supplies they are comparable to wizard coin supply, jp's corner etc.
Awesome! I was a bit apprehensive when Preston showed me their "deal of the day" and it was for a 1972 mint set for a PENNY. I would have rather paid with paypal, but ended going through with the transaction after I found a coupon for first time buyers. I added a 2009 S nickel proof, and 2009 BU's from P & D and my total with shipping was under $9. I'm pretty excited about the nickels. I'm holding those back for his birthday.