I use lipo's in everything now, I like the charge time, I use a 2100 3s in my 9z tx. been going great for over a yr now.
They are exspensive but once set up, they are so convenient. for my planes I use a small 450 3s TP battery and the castle creations 10 bec between it and the rx, the bec and the battery still weigh almost the same as my old 350 nimh batt's I think there is 4g difference and I get way more flights out of the setup than I did with the old fashion bateries. The switching bec converts the higher voltage into 5.1 volt without heat build up. on my Helis, I use the 1320's and get 8 flights on digi sevos in my furys per charge. so convenient.