IMO, avoid coresound, I have had real bad luck with them on 3 service issues. Loooooong turnaround time, not answering e mails, etc. Plus, I think that they put their gear together poorly. My "binuaral mic" set went down on me 3 times, first on warranty, second and third on my dollar for the fixes. Each time the time I sent them in to the time I got them back was 3 + weeks. Like I said, my experience. I have some friends who swear by their products and service. When I got my 4061's, I did the EBay thing. Any one of the reputable dealers will work on mics purchased elsewhere. I got the set, and got it all configured for high spl shows for under 500. If you think that it's a better deal to pay 1100 for new ones, you got a lot more than I do.
good luck!
ilduc