The great thing about the DNA200 is profiling. You can have up to 8 different profiles for different coils. For those who like to make their own coils (like me), it's not possible to compare them. I do like the RX but that is only due to having 3 batteries. Other than that, ist a standard TC device with ok settings. With ok, I mean just that ok, since there are alot of devices with better tc settings than the RX. But when it comes to tweakability, DNA200 is the best device so far I have used. You do not have to be linked all the time to use it, alas, you need to link it up to load new values into profiles.
The other great thing about the DNA200 is that, there are other metals out there to vape on, or different purity's in the metals. With DNA200 you can do that. They are however working on an softwareupgrade on the RX to implement TCR ( or so I'v heard)