MSI.
I also tried Intel DP35DP and it could be updated from Win but it had less options for clocking etc. Otherwise a good board except that sleep mode didn't work at all despite BIOS update. Its not a biggie really but I like to turn off my comp when not in use and I don't like waiting for boot up and thats why I like a working sleep mode. Actually I have heard that many boards for Intel processors suffer from sleep mode not working. Not sure if it is an Intel or Vista issue but I never had such problems with AMD.
And BIOS update is not such a big issue anyway, as you do not need to update it daily or weekly or not even montly...
I have no experience of Gibby boards but I'd imagine they are slightly better quality than MSI as a whole package.
-C+