Most certainly they will be worth less, but I don't think they will drop to near zero in a month. I was throwing that out there a s point of reference, not specifically suggesting selling on eBay. I actually sold one small miner on eBay and it worked fine -- got a good price and all -- but I gave up after that, and went back to selling at lower prices on the forum for BTC. Too much stress to deal with all the ways I might get scammed by buyer/eBay/Paypal.
The mine-to-own concept is a fine one.
EDIT: I'd consider doing it mostly to help out the group and I have cheap electricity, but part of the deal would be that I supply the PSU, as I don't trust the BFL PSUs anywhere near my house.