I sold some domains with GD. Most of my domains are make offer, while there are some at BIN price (lower-level domains).
I don't like the 7-day auctions simply because most domains won't reach their full price potential with this method.
As someone said here before, a good domain will sell itself. I've seen it on my portfolio. Plus a make offer option won't leave as much money on the table as the 7 day auction.
IMO..