We used 12 minute levels (H is a level, O is a level....), 25K in chips, and the following structure:
http://www.worldseriesofpoker.com/st...t/Event20.html
We didn't start losing people till the fourth round of HORSE, and it was all over early into the fifth HORSE since the two remaining players agreed to split, as opposed to duking it out for another hour. You may want to bring it down to 10 or 15K in chips for a single table (and let us know how that works for you).