Well having a 1366x768 screen is about only 51% of the 1920x1080 resolution. So you'd have a huge different if your looking at pixels. Ideally I'd get the 1080P monitor to be a bit future proof even though 2k & 4k monitor's are almost affordable for the average Joe!
Obviously if your pushing video games on a smaller resolution you'll get higher FPS (Usually), but knowing most computers and customers configurations 1080P is more of a standard.
A little insight: I owned a HP W1358 Monitor it had 1366x768, mind you was amazing at the time (7years ago) I used to think it was the latest and greatest until full HD 1080p came out. Overall, my Netflix shows & digital movie library never looked so good!
Regardless if your thinking about...