First let me say that I am happy with this tablet. The screen is amazing and the pointer doesn't 'drift' when it reaches the edges like some other tablets. The brightness on the screen appears to control the backlight and it can be set super bright for well lit rooms, which is great. You get 2 pens which is nice. mapping 16 keys to the front panel is GREAT, i've stuck stickers over the top and drew icons for what i mapped them to which helps. The color is very nice too.
Some people have mentioned a thick nib, and also that the nib moves a bit. Compared to my old Wacom this is a non-issue during drawing. I've also seen people criticise the amount of force for really light or really heavy strokes. Firstly, i'm pressing really really lightly and it still picks it up and draws a very thin line. You can also calibrate the 'full' pressure in the driver so you don't need to press hard, though i haven't needed to. I wouldn't worry about people saying things like that.
The only real issue is the parallax, and lag. Coming from a wacom device, I didn't even know this was a thing. It took at least 20 calibrations to get the cursor to sit where I would think acceptable under the nib. Once you've got it sitting where you are happy with, it becomes tolerable and I have been able to transition fine.
The lag is harder to transition to. When you use a mouse on the screen, the lag isn't there, so it's something to do with the pen input. If you make quick strokes or just hover the pen over the screen and move really quickly, you can see the cursor will fall behind. if you make multiple quick strokes with the pen like hatching, you'll see a hook on the lines. This is because of the lag. The arrow is still catching up from the previous stroke so when you press down you actually start drawing out the return lag of the cursor. You just need to draw slightly slower to compensate.
Once i transitioned past these differences, I really love the tablet. This is coming from a Wacom 12ux. It probably helps I never used a 22HD. I would recommend this device for others considering the price makes it a very capable device.
PS: Photoshop 2017 will only work with this pen properly when set to compatibility mode windows 7. Took a while to work that one out.