AR7100 or AR9100

[Gizmoman]

I'm considering purchasing either the 7100 or the 9100 for use in a turbine helicopter model. My preference is for the 9100 because of the dual battery redundancy. A VR5203 dual voltage regulator will also be needed to supply 5.2V for the gyro.
Except for the lack of dual battery capability, the 7100 would be adequate and eliminate the need for the VR5203.
I'm interested in opinions/comments from anyone who has experience with these receivers.
Regards,
Giz

[John Cook]

with that much $ tied up in the heli the 9100 would be my choice, and run the regulator for the gyro and tail servo. Plus you have more sat rx's :)
the R1222 would be a better choice for just a bit more as it has one more sat rx

[BarracudaHockey]

You can plug another battery into any open servo port or a Y harness (if you're going to do this you can use the gyro gain line safely)

[John Cook]

You can plug another battery into any open servo port or a Y harness (if you're going to do this you can use the gyro gain line safely)
very true.

I guess some other things to consider..

Both have "soft switches" so that if the switch fails you are still "on"

The 9100 you can run dual EC3 or change the connectors and use dual deans in vs the little tiny regular RX connectors. Personally, with that kind of $ wrapped up in a turbine heli I'd feel safer with the dual power in via the 9100 vs just plugging in two powers to the 7100. Also, more sat rx's of the 9100 would be some piece of mind.

Either way I think you have a decent path. My own 2 cents is the 9100 would be better with the regulator. As Barracuda said though, you could do it as well with the 7100, but I would probably add another sat Rx to that combo.