Personally I stay away from AMD (with the exception of GPU's) so my experience with these is somewhat limited. Being a Gigabyte board I would however hold it in high regard. Some reviews I have come across are:
Pros: gigabyte quality manufacture and engineering
Cons: layout of the PCIe slots is wrong.
I know they are trying to stay within ATX form factor, but the little sister of this board, UD3, GA-990FXA-UD3 has a better topology.
If only the x4 slots on the UD3 were x8 it would be an amazing board. That is what I was hoping for in this board. But it is not to be found.
You have to go up to the UD7 to get two X16 and two x8 on one board. And for most applications this is only marginally better than 4 x8 slots.
Pros: Very good voltage regulation. voltage droop is VERY tolerable, unlike some reviews have been saying.
I have achieved a very stable OC on my 1090T with this board. 3.8Ghz @ ~ 1.40V Vcore(peak load after slight V-drooping). The board this replaced required 1.45V Vcore for the same clock.
NB and HT OC'd to ~2.2GHz @ 1.2V CPU/NB voltage and 1.15V NB voltage (i forget the HT voltage).
All motherboard temps stay below 50 C in a case with good airflow and with generally warm ambient temperatures.
backup BIOS chip will be very handy. I have had corrupted bios chips in the past.
3-Way SLI (x16, x16, x8) at this price is very very lucrative. Gigabyte has placed this motherboard very well.