am either going to do the dual pack set-up for more redundantcey or just go back to using Duralites in my pattern planes. I am leaning toward using 2 TP-1100 Lipos, any suggestions? It was suggested to me not to use Lipos with the 4-stroke engines as their are many reports of battery fatigue resulting in failures.
I don't know why a LiPO would fail in a 4 stroke powered model unless it's not being isolated from vibration. I've been using LiPo's in 2C powered Pattern models and even 40% gas stuff for several years. My typical Pattern setup is a pair of Tech-Aero regulators, each with its own TP 2S730 pack. Each regulator is fine adjusted to match output with the other, so the packs drain evenly. A failure of one battery will not cause a crash. You should just monitor the voltage of each pack after each flight in order to see that they are each coming down the discharge curve as expected.