Our last 9930 hybrid I thought was better on battery than the recently leaked 340. And there have been a few bugs reported with that leak. So in the quest for a better battery, we have put together a hybrid consisting of close to a full OS of 342 files. For more info and the download link, go here and grab it.
You need 188.8.131.520 to use as a base. Some of the links you may find are dead now, but try this link it still seems to work.