Food for thought: Just because Whistler offers free upgrades, doesn't mean they work as expected. The DMR/NXDN upgrades do not properly trunk track. The Whistler simply scans the voice frequencies. For small systems this is no big deal, however on larger systems it could be a problem. Be advised, the TRX-2 has it's problems. You can find more on those by searching the Whistler forums. Long story short, it has squelch issues and IMHO, scans much slower than it's hand held counterpart the TRX-1. I have a TRX-2 I rarely use.
Now, I am in no way bashing the Whistler scanners. I have a TRX-1 I use every day to monitor the StarNet P25 system. It works well on that system, especially since I can actually track the PSP talk groups in my area. Even though they are encrypted, the TRX-1 will not skip encrypted transmissions like the Uniden will.
That said, I always turn to my Unidens to listen to DMR and NXDN since they do properly trunk track.
Not trying to scare you away from the TRX, just giving you the info on the "free upgrades". You don't need to buy an SDS scanner either. If simulcast isn't an issue, the Uniden 325P2 is a fine little scanner which can be had on Amazon for about $340.
Amazon.com: Uniden BCD325P2 Handheld TrunkTracker V Scanner. 25,000 Dynamically Allocated Channels. Close Call RF Capture Technology. Location-Based Scanning and S.A.M.E. Weather Alert. Compact Size.: Car Electronics
You could probably get the 325P2 and both DMR and NXDN upgrades for about what you would pay for the TRX-2 on Amazon.
Keep in mind, if simulcast is an issue in your area, neither the TRX series or the 325P2 will work very well and you'll probably end up with an SDS scanner in the long run.