I did the 10k for the livestrong. It was a pretty good time. It's right in downtown Austin, and at a good time of year. I think the weather was in the high 50s or low 60s at race time.
The race was well managed. I picked up my packet the day of, got a t-shirt, bib, and chip. Overall, it was a pretty on par, city, road race. The one benefit is that the field was pretty small so it wasn't too crowded.
I think the only main issue I had was the course layout. It's an out and back 5k course, so if you do the 10k, you do the out and back twice.
Lots of people do the race for the cancer charity, which is super cool, and I totally support. But, it means there's lots of walkers. And what happens is if you're doing the 10k, during the 2nd lack you're trying to navigate your way through a crowd of groups walking.
So, if you're out there primarily to support the cause, I think it's a great race. If you're out there to get a PR in your 10k, well, you might run into some issues trying to work your way through the crowd.
Still, overall a great experience and well organized.