I recently sold all of my clad proof sets for $115.00. I made no money on the deal, but I don't care because I got tired of looking at the valueless things.
I pretty much did the same thing years ago, but I also sold my silver sets that I had back when they still had some premium value under the State Quarters program. It's too bad because I actually liked the sets, but they started to pile up and take up too much room and, as the OP said, their low value ultimately didn't justify the space they took up. I also wanted to sell them before any premiums diminished, which by now they largely have. Oh well. I still buy the occasional non-US proof set and I try to buy a set of coins from other countries that I visit, but apart from that I'm more or less done with that genre.
