HELP QUICK!!!!!

[shortpballer]

Hi, I put my 17-55 2.8 on craigslist. Someone offered me a trade for a 100mm macro and a MR-14EX Macro Ring Lite. Should I take it? I don't think I will use the ring lite since I will be doing portraits with the 100mm. How much is the ring lite worth used?

Please help me out, if I do the trade it is tomorrow, so I would like to know before then.

Eric