1. I wasn't shipped a lemon, so I can't testify as to what happens if you get one. That having been said, the person I bought from had tons of 99.8% reputation and I swear, I have no idea how it go to my doorstep from China so quickly (custom stickers and all indicating it erally moved that fast).
2. I have no idea why HD4000 won't drive that 2560x1440 resolution over DVI/HDMI. I just know that HD4000 has that prowess to output it and I read somewhere that it only works over DisplayPort. So far, based on my HD4000 MBA and desktop, that seems to be true. I'll see if I can find you a source on that.
Oh, I thought you meant that it was a limitation of the screen. That's a relief, then. I have currently had a 22" LG for a few years, it might be time to get a new screen!
HDMI 1.3 supports this resolution and there are numerous sources that indicate that the HD4000 will not drive a 2560x1440 resolution over a DVI port. Also, me and everyone else with a Dual link DVI port and HD4000 will tell you that it flatly doesn't work.
2. I have no idea why HD4000 won't drive that 2560x1440 resolution over DVI/HDMI. I just know that HD4000 has that prowess to output it and I read somewhere that it only works over DisplayPort. So far, based on my HD4000 MBA and desktop, that seems to be true. I'll see if I can find you a source on that.
edit: This is not the exact same ebay listing, but is from the same person and is the same product that I purchased: http://www.ebay.com/itm/New-Crossover-27Q-LED-P-27-DVI-D-Dua...
edit2: Sources on the HDMI/DVI/DisplayPort discrepancy: http://communities.intel.com/message/160909#160909