Anymore I use NIMH batteries for the most part but if/when I can find them I like the NICAD. Just because they take the heat of fast charging better. GA, I almost always get the biggest packs I can but sometimes I have batteries standing in line waiting for A charger that will charge them all the way. I have three chargers plus my fast field charger.
I love my old Ace DIGIPULSE because I can charge 6 batteries all with different mAh requirements but it only goes up to 1500 mAh before it goes into trickle mode. My Accu Cycle was OK as A charger but it never did work very well as A discharger, sent it back but was told it was OK, so much for Tower junk. I then bought the H-9 Sure Cycle, outstanding machine does the TX and RX batteries at the same time. Because I fly so many different planes and used to fly big events for several days at A time I also have the H-9 Double Vision Fast Field Charger. I have it set up to plug into any cigarette lighter or computer auto outlet.
My flight packs also vary. I mostly have 6 volt NIMS running about 2500 mAh but i also have some big 6 volt 4200 mAh NIMs in Sub -C with two wires. On some of my bigger planes I needed the weight so the Sub-Cs, I have also had switch problems in the past so the two wires for double switches. I have run the redundent two battery systems and like it but it depends on my plane. For GAs up and comming new pattern plane the two 6 volt two switch system is over kill but could be A good idea, could also be A 4.8 volt system too. i I also have two battery testers in my flight box most the time, I do use volt watch on some planes or the GEM 2000 but I still test before each flight even if the VW is stating good!!