Yes, adding the glare-guard improves the LED display 2x. Removes the light reflecting off the LEDs from the PF and knocks the over-bright colors down so they all appear uniform. They should sell these with the displays IMHO.
Comparing the 2 well, using Hi-Rez mode on a 90s game is a travesty IMHO. I greatly prefer the Dots setting on the LCD. The LED here looks fantastic!