I'm not currently in the market for a monitor but this one checks all the boxes for me. There are very few reviews for this (although there are a few on Amazon if you want to check.)
31.5 inch
144hz
Freesync
4ms response time
Curved
Vesa mountable
$350 shipped (but tax applies if you're in NY or NJ)
https://www.bhphotovideo.com/c/product/1425396-REG/acer_um_je3aa_a01_32_ed323qur_curved_31_5.html
31.5 inch
144hz
Freesync
4ms response time
Curved
Vesa mountable
$350 shipped (but tax applies if you're in NY or NJ)
https://www.bhphotovideo.com/c/product/1425396-REG/acer_um_je3aa_a01_32_ed323qur_curved_31_5.html