This thread may be better off in the Consumerwatch forum with a title like 'Which 21-24" TFT monitor?'
Anyway, to get you started there's some good info at click here. CRT monitors are also mentioned to give a more balanced perspective.
What are you going to use the monitor for, & what's your budget?
If you have a few models in mind, post the links here & some of the monitor boffins may be able to suggest which ones may suit you best.
Here's a list of TFTs, 21" & above (sorted by ascending prices)
I may not contribute any more to this thread (I'd probably consider a 21-24" TFT sometime in 2020!), but this post will shunt you up the list & hopefully elicit some informed responses. Good luck with the eventual choice & purchase : ) G