We did the VA on last year. It was brutal. The obstacles weren't that hard, just the whole event was tiring.
One obstacle was at the bottom of the ski resort, then you had to run to the top and do another one, then back to the bottom for another, and so on.
They had this dumpster filled with ice water. They had this tractor keep dumping ice in constantly. In the middle there was a board with barb wire on top, so they made you go underwater to get past it. It kicked my ass. Mentally, i was still fine, but physically, i couldn't function right. My arms and legs wouldn't work right. It sucked. It was only 30 feet or so, but damn.
They had hay bales set up in a sorta maze like area and they set them on fire and you had to run through the maze. The heat was bad, but the smoke was awful. It was just long enough for you to get through before the smoke got the best of you.
There was this 10,000 volt shock field thing at the end. It was muddy, slippery and there were hundreds of these wires hanging down. You had to run through the wires in the mud. Each wire would shock the shit out of you.
If you think your a tough guy, check it out. Give it a try. Its brutal, but awesome at the same time.