Yup, and if looking at cheaper, lower wattage systems the big thing I'd look out for is maximum frequency. A lot of the lower power systems that should be able to support dusting settings (say 50hz and 0.2j, for only 10watts) do not support higher frequencies which limits your options in cases where you don't want to pull out a bunch of fragments (small ureter/sheath, etc)
Incidentally, for those on the Thulium bandwagon, have you started adjusting your patient counselling in terms of URS vs. PCNL? I've found the thulium makes quick work of the ~2cm dense stones that I used to steer towards PCNL. Sad, because I like percs, but such is progress. I see a near future where percs are really only for the true staghorns and mini-perc disappears except in cases where retrograde access can't be obtained.