I run A123's in my B44, as far as I'm concerned they are the best car cell on the market. Lifespan is 3 times more than any NICD/NIMH and 4 times more than lipo, they are very safe(no fire) and tolerant to overcharging and overdischarging. Cheaper than lipo but a little more than NIMH per cell but you need less of them so in the end it's cheaper. The voltage is a bit lower but the discharge curve is very flat so NIMH may have a bit more voltage to begin with but after a minute or so they will be about the same and then a few minutes after that the A123 will have more, lipo's have a fairly flat curve but not as flat as a123. If your running a low KV motor you might notice the lower voltage but with a high KV like the 7700 only the radar gun will know. Charge time is also great, the 2300mah cell can be charged at 10 amps so 15 minute recharges are no problem, I can produce some links that show them being fully recharged in 3.45 minutes over 350 times with only the slightest loss of capacity. As you can tell I love my A123's and a side note the 1100mah A123 cell work great in my associated RC18R........BB