I have the 22'slx, but was a confirmed 17'xtel person.
The money saving/making part for me is not having to get my stepladders off/swap poles so often. The brush has been superb and has the high flow fans which look and sound great.(they spray water over a wide even area and make a satisfying shishing sound).
My vikans have always had fans but these are in a different league and suit my style.(i use lots of water but in return am able to work very fast and make very few errors). I can't believe you came up with such a good fan when i'm pretty sure you don't rate them.
The chap who helps me is also a big fan of the brush and jets and because he has no background in this all he has to guide him is his own commen sense and what's easiest for him.Because of this i respect his opinions.All of my xtels and vikans, and i have quite a few, are now just ornaments.
Despite what you say i do think brittleness will be a problem, i'm thinking when it's cold and going over roof or cons the clamps are banged into something. I am very clumsy, and when i am working it is all about speed.The xtel clamps are more 'whack proof' because of rounding in the design and i think there is either still some slx evolution to be had-or else- easy and cheap access to spares is needed.
Speaking for myself i find the poles terrific value for money and want everyone in my team to have one (okay a new starter would be on an xtel for a couple of months) because of the benefits.But i also want to administer a 'quick fix' if they get knocked about.