There are many little features that stuck out here when getting the ASRock X399M Taichi up and running, like that right-angled audio header and the additional pin header for the three-pin-spaced front-panel power LEDs my Lian-Li test bench needs.
With the memory slots and CPU socket so close together, you do need to keep in mind fitment issues with fans and larger DIMMs, though I did manage to squeeze my large-ish G.Skill Trident-Z RGB sticks under the fan of the Arctic Freezer 33 TR fairly easily. When looking at this, I noticed that I had not plugged in the 4-pin CPU power connector. It's not required, but if you are overclocking, it can help with keeping the board a bit cooler as the drawn power is spread out more.
This is one of only a few boards to have M.2 ports on the side of the board, between the DIMMs and power plugs I have played with so far, but I really like this port being accessible so easily as it made swapping drives out for testing a breeze. Plus, with the airflow from the CPU fan drawn over that area too, there's more than ample airflow here for some of those hotter-running PCIe SSDs.
The ASRock X399M Taichi seems to run with a slightly elevated base clock and a lowered Boost Clock at first, but the clocks seem to modulate quite quickly under load. I was rather impressed with the Arctic-designed cooler's ability to keep this crazy dual-die CPU cool even though the heatpipes do not touch the surface of the Threadripper CPU completely. I didn't seem to run into any memory compatibility issues either with this board, and considering the problems the Ryzen platform can have with memory at times, this was definitely a welcome ability.