Jhautz: I was thinking new Spektrum vs old older Spektrum, not other radios. That makes sense, older technology is almost always less efficient than newer.
The size and weight is certainly a lot less than the DX2/3/2.0/3.0! Not only that, but the reduced weight on top makes it less top heavy - not that the old one is bad, you just notice the difference when holding both.
The 2.4 security is nice, and it's sure easier than carrying crystals when at the races. However, the main reason I got mine is the 30 model memory.
MetalMan: I've already thought of that. I am a little hesitant because what if I do accidentally leave it on and don't hear the buzzer? I would rather have an LVC than a LVW (low voltage warning). The latter is passive protection, the former is active protection. I have a LVC circuit idea that I might try.