Honestly? If you already have a desktop or would prefer a tower/desktop system, just get that and get a Cintiq HD digital display (those are the ones that are monitors you draw on, vs. the Cintiq Companion being a full computer).
I was in a situation at the time when I got the Companion 2 that it worked for me - I spent a lot of time at work (Starbucks) aside from home so having the portability was nice, and my laptop had died so I needed a new computer.
So those are the pros in my specific situation, with the fact that it's also a digital display tablet. However, if you like having the ability to customize your desktop (assuming you're using a desktop which you can take apart and install new graphics cards/HDD's/processors/etc.) and not be stuck with 100% intel products, it might not be for you. Also, if you already have a computer, there's really no point in dropping more cash on a second computer when you could just get a Cintiq HD which does the same job but only operating as a secondary monitor. Not only that, but because it's a tablet that you can't take apart, if it breaks? You're fudged lol Not a lot of people around who would know/be able to fix hardware issues.
It's super expensive, I'm talking like, $3000 for the standard, most well-balanced model (the one I got). You could get a desktop computer for much cheaper, especially if you build it.
My personal recommendation? Build your own computer. Get a Cintiq HD digital display tablet. It'll probably be cheaper for both those things than it would cost to buy a Companion 2.
If you can't/don't want to build your own desktop, then find one you can get that has a decent processor, CPU, and graphics card, and look into getting a Cintiq HD.
Final tip: Drawing directly is nice, but don't underestimate the power of an Intuos Pro! A lot of them share the same specs with Cintiq HD's, sans the direct digital display drawing - if you can get the same results, the digital display is really just a luxury bonus.
Sooo yep, that's my analysis of it. If you have the money to drop on a Cintiq Companion 2, do what you want with it, if it's something you'd want
(I also had the advantage of student loans money to cover it lol) If you do get it though, DEAR GOD make sure you get the Cintiq Companion 2, NOT the first model - the first model is literally a tablet in the sense of being like, an iPad that is capable of drawing. It sucks. It's suck incarnate. The Cintiq Companion 2 is the definitive better model because it's its own computer, with the Windows OS (so if you're a Mac user, might not be your thing, as it can't run iOS at all) and all the functions of a normal run-of-the-mill computer.
Hope that helps! <3