XL4 does require a few special tools for the 2nd stage - a subset of the Flight special tools. If you don't need coldwater, Mikron is probably fine rather than XL4. (The XL4+ just adds a 2nd HP port, and everything is white.)
Just one note to consider - in general, smaller compact 2nd stages usually have a higher Work Of Breathing than larger 2nd stages. Often that difference, while measurable on an ANSTI machine, would never be noticed by the diver except in extreme conditions. (depth, higher rater of breathing, etc.) So that is not a game changer, just something to be aware of when making an informed decision.
