“Best” is a very subjective term. In my experience, just about any monitor will do as the mirror layer is going to interfere with what normally separates one monitor from another.
To me, the absolute non-negotiable feature is at least one HDMI port and it must face down towards the table in a normal configuration. Other than that… Resolution doesn’t matter so much because I’m just displaying text. Refresh rates don’t matter. Vividness of colors likewise doesn’t matter.
I would look for one with good black levels, as any backlight will show through a little bit when the monitor is on. Other than that… whichever is cheapest for the size I want.