1: I agree with the others, and get the upgrade keys directly from Uniden. It's much cheaper!
2: I have all 4, in that I bought mine second-hand, with the three original upgrades already added, and I bought the waterfall. I would absolutely recommend getting the DMR and NXDN options, and get the waterfall option if you want to explore a bit (it's fun and can be useful, but not absolutely necessary), and get the ProVoice only if you think you'll be going somewhere that might actually be still using it. (I'd still get it, "just in case", and not to feel like you don't have all this scanner's options available, again, "just in case".....

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