I've actually had a few different nRF52840 boards to try and get started with the line of Nordic SoCs, but this was the one that got me not only digging in, but absolutely enjoying it. It's 100% functional right out of the box if you want to play with Python. But the real key is, MakerDiary has already ported several examples from the nRF5 SDK, and Zephyr to take advantage of the M.2 Developer Kit's specific hardware. Those examples build with zero issues and have been plenty enough to get me going in the directions I wanted to. Plus, many of the nRF5 SDK examples work directly with no to little modification too! I literally haven't taken it off my desk since I've started playing with it.
If I had wishlist features for the next version of the dock, it would be a breakout for the SPI lines that the SD Card and IPS share, and maybe a few different default pin assignments on the nRF52840.
In conclusion: I don't know that you'll find a more capable dev kit for this price, and certainly not one that's packaged and delivered as well as this one is. If you're on the fence: Buy it. Right now. You'll be glad you did.