I don’t use the official dock, but I use the JSAUX one. The only reason why I have it is because I can play on the television, sit the Deck in the rest, and it doesn’t fall over or off the TV stand.
That, and I can leave the dock plugged in, and not have to keep plugging and unplugging cords all the time.
If you are treating the whole setup like a station, then it’s quite useful. If you’re treating it like a hub that you’re going to plug and unplug cords often, then I don’t suggest it.
Honestly, I’m not computer proficient at all. The most I’ve had to do anything on the “computer” side of the Deck was to set it up the first time, and when I installed the 1TB SSD upgrade to the LCD Deck. If that’s the most I have to do to play games, then I’m happy.
I’ve never once had to go into desktop mode to do any tweaks or tricks, but I’m sure there is a crowd of people who say you will come across it.
Do I suggest you need to check it out early before Christmas? Yes and no. If you plan on returning it, yes. However, Valve is great with making sure any technical issues get resolved if you wait until after. So, they’ll try to give you the best technical experience (personal experience is all on you, though)