I'm using version 1005B right now, and my system has never been more stable...
I was one of the first people to get the rev1.02 A7V, and I think I started at bios version 1002 or so...went to 1003 and tried C (worked well enough), 1004C and 1004D (D was very stable), decided against 1005A because I heard some bad things about it, and am currently using 1005B
The only reason I haven't switched to 1005C yet is I heard some negative things about it...think I'll wait for 1005D