Tried it twice last year with the same 25dates company. First time I went alone and felt like a loser. Second time was a freebie (if you didn't choose anyone the first time around), and I got my cousin to tag along. She's very attractive and was quite popular that night. Anyway, I enjoyed this one much more because you know what to expect and say in these awkward 3 minute windows to gauge someone.
Things to keep in mind...Like Afterhours said, lower your expectations and don't be picky. 80% of the girls are what most of us would deem "average" or "below average" in appearance. And yes, a lot of them are larger ladies. But most of them were genuine and very nice. Conversely, there were some major hotties there who would have no problems finding dates. I suspect some of them were there to accompany their less fortunate friends, or just to mind-fuck the dudes that attend these things. It's funny to watch all the guys ignoring or rushing through their "dates" with the less attractive girls to get to the hot one, and then trip all over themselves trying to make an impression.
Another thing I found interesting was that a large proportion of the girls came from 2 professions: teaching and nursing. Practically all of them said their professions were not conducive to dating hence this method of trying to meet people.
But all in all, I enjoyed myself. I took it for what it was - a social activity, and not necessarily a vehicle to find a meaningful relationship.