Not a fan of them...

If you don't have the money for an item, why bid on it or submit an offer? You are wasting everyone's time, not to mention, that there is probably another person that would purchase the item and actually pay for it!

What really sucks is that now FeeBay no longer penalizes buyers they way they used to for non-payment. In the good ol' days, you were actually able to leave negative feedback for non-payment, now you can't, and the buyer's rating is no longer affected. If you were a third party looking at the seller's and buyer's feedback, it's like it never happened, thus you would think the buyer is reputible. How could you tell that the buyer doesn't pay for items?

In closing, stop wasting people's time. If you don't have the money or the means to pay then and there, you shouldn't commit to things you can't fulfill.