I built the smaller version and it flies well. Lost one, one time after I put too many C6-7's through it. Disappeared I think into a pond.
Putting the largest motor in, do it only on a rare windless day.
With the small version the rocket would disappear into the ether and I'd wait and wait and wait. When I was about ready to give up, I'd hear the rattling of the mylar streamer I used. I highly recommend looking online and getting a reflective mylar sheeting streamer material for the small Hi-Flier. Pot growers use the sheeting to reflect light in their "growing" rooms. Flashes when one can see it and makes a rattling noise on the way down one can hear if they are flying in a field by themselves without too much background noise. One roll will last you a lifetime. I built another H.F. and still have it.
I imagine the XL uses a chute though since it's a larger sized rocket? I'd see if it could be modified for a tracker if planning to send it "stupid high". If using lower impulse motors for leisurely flights, shouldn't have a problem. Like a Big Bertha on a B6-4 or C6-5, always a satisfying flight and always get it back if no trees, standing corn or wires around. Kurt