How much would you be willing to spend?
Anything that has a 178º viewing angle means it doesn't have a TN panel.
TN panels are cheap to make panels that only use 6 bits per colour channel, and can therefore only display 262,144 colours (as opposed to 16,777,216 colours of an 8-bit panel).
They attempt to mimick more colours by using methods such as dithering, and switching between two colours rapidly. But the end result is not the same as actually having an 8-bit panel
The types of 8-bit panels are IPS and VA, with subsets of each (including S-IPS, H-IPS, MVA, PVA)
So far it is impossible for a TN panel to get a viewing angle of 178º, so that's the easiest way to tell if it's a TN panel or not
I've heard good things about the HP LP245w. It's got a H-IPS panel, which is one of the best - and doesn't cost that much compared to most IPS monitors.
Newegg.com - HP LP2475w Black 24" 6 ms (GTG); 12ms HDMI Widescreen LCD Monitor 400 cd/m2 1000:1 w/ Height/Pivot/Swivel adjustments - LCD Monitors