Given what is out there right now, you basically have two good options:
2400 cells (Sanyo)
3000 SMH cells (Pansonic (stock metal hydride))
The 3000HV cells from Sanyo will probably -- in my opinion -- be similar to or slightly better than the Panasonic SMH's. Right now, I don't think many (or any) of them have made it to the marketplace.
So if you want the 3000HV cells you could always wait, but if it were me, I would go with the SMH cells from Panasonic. I have a few packs of these, and they are great! Plenty of runtime, and voltage comparable to 2400s, plus you can charge/recharge them multiple times during a raceday.
What's not to like?