Rock N Roll races in my opinion are a catch 22. They are super fun, but super big. You'll be in the chute aiming for a 1:45-1:50 and the people in your chute are in the 12 min mile crowd but guessed their finish time incorrectly and are hoping for a miracle. Nevertheless, the crowd support at these races is amazing! The local bands at each mile are awesome and loud! And keep you going. This was a great race to do with girlfriends. We all were looking for a fun time.
Likes about this race:
1. great crowd support
2. great expo
3. nice swag
4. fun afterparty
5. not too hilly for San Antonio

Dislikes:
1. crowded
2. parking is obsolete
3. volunteers rush you out of the finshline area to make room for everyone (I understand but catching your breath and taking a photo with your medal is nice)
4. It's nearly impossible to find your friends afterwards (even if you come up with a meeting spot (it's just that huge)
5. weather is unpredictable

I've done this race in 2011 and 2013 and it's one I like because it's my hometown but there definitely are things to consider if you are making it a destination race.