do you NEED a ‘mirror’ in the kitchen?
One more vote.
32 Inch Monitor (I read that VA panels have better black levels so decided for this one): $271
Wow, the monitor itself looks really good. But in my opinion, it’s somehow overkill. Generally, MM and your Pi don’t need such a high spec: 165Hz, 1ms, … MM is not game machine or Netflix player.
And if you really assemble Spymirror on your screen, you may lose some of the benefits of those high-class monitors.
A bigger screen would be heavier. It needs more robust frames and mounting methods, and thermal control must also be considered for that kind of monster.
Even though RPI 4 can handle up to 4K60p (3840x2160), It would be a burden for RPI4. If you are considering playing clips on your MM, you may need a stronger device.
So, what is your purpose? Your types of equipment would depend on your needs.