Anyone know if Hitec 7955 servos work OK with 2S LiPo power or should I use a LiFe battery instead?

I'll be using a Futaba R2104GF receiver if it makes any difference. It's supposed to handle up to 8.4v

The 7955 isn't rated at 7.4 so you are on your own there. It is rated for 6 volts regardless of the receiver.

What is the best way to break in a 6.6 liFe Rx battery?

No break in needed. Just run it!!!

get a 7954sh instead...it's rated for 7.4V and almost the same specs as the 7955..

I thought for the first 20 charges they do not like being run under 3.26? They have a tendency to puff or not hold a charge

Nominal voltage of a Life cell is 3.3v so that doesnt sound right

I would keep them above 3v for a couple of cycles, then go for it

Cheers

What I am saying is that once charged to 3.6 per cell, letting them discharge to 3.26 before 20 cycles, they can easily puff and lose a charge unexpectly.

Just charge and go. They are sturdier than Lipos. I have two that are three years old and still going strong. I even discharged them below 3V unintentionally and no problem. Both are in my pan cars and take about 50 to 60 mah per heat/main.

Sounds good. Thanks

Thanks very much for the info. I will probably do an exchange for the 7954.