Sorry for the repeat, but do you think I can use a 1400 or 1500ma NiCd battery for the Rx in my Giant Sportster? It has 5 Hitec 645's and a Fut 3004.

I'd like to stick with NiCd because of the higher self-discharge rates with NiMH. Does this make sense?

I would not, For me I would use a LI ON , or a LI PO with a regulator (4000mah). But that's me . It would work , but I would check it after every flight with a load tester . It really depends on how you fly. I fly hard and really give a plane a work out, and that would use the battery much faster and have a higher demand on the battery , than just slow sport flying. TBM says that most crashes not pilot related are related to the battery , some how, like a bad or shorted switch, and or a bad battery of shorted cell, it is often the weakest link, So my thought is why spend all that money in a larger pland and then put a five dollar switch , and a thirteen dollar battery in the most critical place. AND AGAIN this is my opinion. Not a LAW

I think you will be fine with a battery that size. Just make sure they are good cells with a low internal resistance.

I agree - should be fine if check regularly. NiCads are still easy to charge and operate c/w some of the newer technologies, so why not if weight's not an issue.

I fly both. NIMH & Lith with regulates and both work very well, do look at your options and keep close eye on your NIMH cells. I fly a 33% on NIMH cells with 8 servos and one 3300Mah 6 volt pack without problems, I just make sure to keep my cells conditioned and cycled properly with my Triton 2 charger, as long as I keep my batteries cycled properly they last me a long time in my planes. With Lithium they work well too, I have one plane I can fly 15 flights on one charge with 6 servos on a 28% Extra 260 and still be in the safe zone with my battery checker under a 1 amp load, I have flown since the early 80s and have seen the technology come and there are some great things that have come around in battery technology. The new A123 batteries are showing great promise for this hobby, but they have a sudden drop in power at the end of there cycle like NiCad's did, the run time is longer, but I just don't like the sudden fall off if I don't keep a good watch on them. Someday I may make that change but I guess I am too old school and like staying with what I have been using.