LiFePO4 batteries - performance issues running 6.6V?

[colmo]

As a returnee to RC and a newcomer to racing, my research to catch up with latest technology included the new lithium-based cells - both LiPo and nano-phosphate/LiFe(PO4).

The advantages of LiFe over LiPo look good - potentially twice as many cycles, higher charge and discharge rates, more robust and without the safety caveats LiPos come with.

However, the standard LiFe cell suitable for RC car racing, the M1 made by A123 Racing (and now sole owners of Enerland), have a standard voltage of 3.3V nominal. This doesn't quite fit the standard 7.2-7.4V voltage, the closest you can get being 6.6V in a 2S pack.

My question, then, is what performance impacts will this lower voltage have on the performance of a modern brushless motor in a modern RC car? As the voltage is lower, the current drawn must be higher to obtain the same power (in practice, this would be done by gearing up to compensate for low voltage) - are modern ESCs sufficiently over-specified to cope with the extra current?

I refer to this article; it indicates that in low voltage situations, the higher current drawn is not in itself a problem, unless it goes above the upper limit the motor is capable of. As brushless motors can be geared more aggressively than brushed, does this place a lower ceiling for gearing if using lower voltage cells, or risk damage and/or shorter lifespan from the motor?

Torque is also lost with lower voltage (a 10% voltage drop, which is roughly the difference we are considering here, would reduce the starting torque, pull-up torque, and pullout torque to 81% of the full voltage values) - is this as big a loss on the track as it is on paper?