I think I paid around $500 for mine, not sure what its actually worth. IMO its worth less than a lamey cylinder and more than a stock cylinder LOL. It can be a gamble, you definitely run the risk of it being decked for a stroker or ported for racing, etc. I lucked out and as far as I know it was untouched from ProTec, the ports weren't extreme but much better and cleaner than a stock cylinder. I think given to the right person to do some porting it could be a really great cylinder.
I bought mine purely out of curiosity and because I had money to burn, it ran well, I was pleased, I'd like another but probably wouldn't spend that much on it again. Best suited for a rec boat, loads of midrange and topend, it went well in my chan I think because it was fairly light and could rev fast.