Under $300 buys a genuinely good monitor now, but only if you pick the trade-off that matches how you actually use it. Panel technology that was premium three years ago — 1440p IPS, 100Hz+ refresh rates, USB-C with power delivery — has moved down into this bracket, so the question is less 'is it good enough' and more 'which compromise suits me'.
The main fork in the road is resolution versus refresh rate versus size. A 27-inch 1440p panel at 100Hz is the best all-rounder for work and casual gaming. A 24-inch 1080p panel at 165Hz is the better pick if you play competitive shooters and want every frame. Very few monitors in this range do both well, so decide which matters before you shop.
Below are the picks worth considering, the specs that matter more than marketing numbers, and answers to the questions people ask before buying a budget monitor.