I do not have XS but I do have a Large fiber optic front. For short range - I Really like it, the big dot reduces transition time & shot string - as stated by others - rear site is optional n Large front really stands out.
Negative - longer range accuracy suffers but I'm punching paper and looking for nice groups not combat accuracy. I'm going to install smaller diameter lite pipe to see if I like it better.
Note: Tgt shooters have some tricks to squeeze more accuracy out of larger diameter front. ( Durango Kid taught me to use 6 o'clock hold or top edge of circle to aim w for greater accuracy.)