You can only test so many monitors, but luckily, we've seen a few come through The Tech Buyer's Guru. We'll add more monitor reviews as opportunities arise, but we can offer a few pieces of advice that apply quite broadly.
First, all else being equal, an IPS or similar type of panel is going to offer the best image quality, while TN-based panels offer the best motion clarity. That being said, with the advent of Nvidia G-Sync and AMD FreeSync monitors, the way we judge motion clarity has changed, and we now recommend TN panels only for shoppers on a budget. An IPS panel with G-Sync or FreeSync is always going to be preferable. Second, refresh rate has become a real selling point for modern monitors. Whereas LCDs were locked at 60Hz for over a decade, they can now be found with refresh rates of 144Hz or higher, depending on the model. The smoothness of high-refresh rate monitors is perceptible not just in gaming, but for desktop use as well. Unfortunately, until the next DisplayPort specification is released, 4K monitors will remain locked at 60Hz. The amount of bandwidth required to pass 4K resolution at high refresh rates is simply too much for existing cables.