partywagon... don't make me defend craps, dangit!!!!
Lipos have a higher voltage and good cells hold it better than A123s.
I like the A123 cells for some things. They are great for super fast charging and are very safe and last forever. I still have not run them but I do plan to grab a Dewalt pack sometime soon. I have some of the new smaller 1100mah cells to play with. It's the charging thing that has me interested... for a basher vehicle.
But for long races especially.... they get heavy and awkward compared to lipos. I guess a 3p hump style pack would be too bad but still, it's not as slick and light as a 6-8k lipo.
In 1/8 buggy it's even worse... how can you fit a 4s or 5s pack, even at just 2p it's a brick. I figure it would take a 5s3p (or 4s4p) pack to replace my 4s 8000mah lipo.... and that would make my FAT 8000 lipo look small. Only way it could work is running a 2p pack and doing a pit stop.