Older thread but anyway:
My experiences in short form
MSI - fair stuff, low price, well equipped; NOTE that this is my experience with dated Socket A mainboards (which I still use today)
So I can't tell about them today but they HAD some decent stuff. The German hotline (prolly outsourced) was lame though, no technichal knowledge, no nothing. Well, okay, I called one time so I shouldn't judge from that one time experience.
At all I built 4 or 5 boxed with mainboards from them and they've been fair/good stuff.
Elitegroup/VIA in a cheapo laptop (ECS G320) - acceptable for the price
Jetway - huh, dunno... it's prolly all the VIA stuff on it that gave me the creeps, the board is ice cold and passively cooled and all, most things work but then a few things like HPET are broken (Kernel freeze at boot and so on) and that old problem with the FUBARed Chrome-Grpahics by VIA... well. The board is miniITX very low power consumption but wasn't really low on price (but with CPU onboard)
ASUS - was great and prolly is still the same great. I'm NOT fond of their software quality what concerns the W32 software. But since Gentoo Linux comes without any rebranded stuff and is just pure and full of goodness... only few problems and they have decent BIOS stuff. Recent experiences with two boards (2008/2009).
ASROCK - to my knowledge (no own experiences though!) the contents of the litterbox they throw out at ASUS' site is captured by ASROCK and reused for cheapo mainboards. Heard of several one blowing quickly.
QDI - dunno if they still exist, but probably crap, blew a few times on a friend's box.
Shuttle - had one for socket 370 which was nice but the elkos (what's the correct word in English? electrolyte condensators) popped. But that was a widespread issue back at the time. Most vendors had it. Couldn't use it really long.
Yakumo - gave up on biz, it was a Socket 7. HDD controller got crazy after a few years of use. Dropped support so also no BIOS updates available. Meh.
something that was maybe intel?
On my first 486. *bleeds bloody tears* OMG, the good old times... I soo loved that box. Sadly the box somehow doesn't boot anymore. Dahmit. Still I can't throw it away. Could you?
A few others I bought used on some popular auction platform but I don't want to tell about them since I didn't use them intensively and when something is already used... well, you never know what the pre-owner did with it.
I'd also be interested in a HDD comparison.