RE: Using two batteries at the same time
Just searching around for that gyro - one of the nice things is it has both remote AND local gain adjust - if CH5 is not plugged in, you can adjust the gain with the pot (BTW - read where the adjustment is reverse - turning positively DECREASES gain! So beware!) Also the reviewer says it seems to have much less, not even noticeable, drift with temperature change, compared to the TeleBee.
Do you have a link to the manual? Also it is stated it is larger than the Futaba - I would like to know the specs.