NIZN batteries are the way to go, nothing is even close. You have to use a NIZN charger for them. I have seen 4 batteries and charger for less than $20. I also have a spare set of 4 when needed. I put a lipo in my DX3S and it is still showing 7.9 volts 3 months later. That is very impressive and the battery cost like $12. I had to mod the radio and the battery. Soldering a Deans connector onto a battery makes me every nervous to say the least, I took lots of time doing it.