Best answer: Getting a Surface Dock is worth it if you want to use your Surface Pro X like a PC when you're at home or in the office. Otherwise, there's not really any reason to get one.
I've got a pro 3. Been thinking of upgrading to the pro 6 and now 7 i5. I saw Dan's review last night and I walked away with his point about the pro 7 i5 (fanless) is slightly faster than the pro 6 i7.
I'm looking to replace pro 3 with the 7 or x and use this is my main PC/workstation at the office too. Dock it up with multi monitors. I just hope I can still ink on it at same time.