The KeyLab 49 MK3 is a nice keyboard. It looks nice and minimalistic. The control dials and faders have a nice resistance to them. The toch option works great. The big silver dial is not nice to handle unfortunate. Rotation to select a next/previous item is too precise. And when press the dial to select the item, it often rotates to the next item before selecting it one I intended. Rhis cause the wrong item to be selected.
The display is nice, clear with beautiful colors. It is very readable from lower angles.
The pads are too stiff in my opinion. And by default you have to tab very hard to get the max tab value. But this can be adjusted in the settings.
The keyboard is ok for the price. A good enough quality. The afterthouch is a little stiff, though.
You do not need an adapter when using USB-C. This is very great! It works perfect with my MacBook.
Using it with Arturia Analog Lab, selecting another patch is slow. But on a little faster on other Arturia virtual instruments. The sounds of Arturia's virtual instruments are amazing! Specifically DX-7 and OB-X.
I use Logic Pro 11 and the integration is very poor in my opinion. Arturia needs to really improve this. The integration with Ableton Live is much better. I tried customizing the integration with customizating the cc values, but that's really not fun.
Personally I still prefer hardware synths. Feeling the knobs and instant feedback without needing a computer is priceless. But as I mentioned, the Arturia virtual synths sound like the real syths for way less money ;-)