For about the same price you can buy as many sheets as you want directly from the USPS in unopened packets, with the added benefit of getting lucky in snatching a right-side up sheet. Why would one with smarts go buy from an
ebay seller with all the sheets opened and handled?
As far as varieties go, the print control on these sheets are so bad that one has a much better chance of picking up a flawed sheet randomly than a perfect sheet.
I have so far opened 6 packets in total, and every sheet has stamps that contain some sort of flaws (over-inking, under inking, missing ink, red wheel, truncated wing tip, etc.).