The Stenlight has one big drawback (for me, at least): its magnetic switch that throws-off my compass by several degrees. This is the only reason I don't own one.
The Scurion does not have that problem, but I don't think that you can mount another light below or above it on a helmet. (And mounting lights on the sides is a no-no for small caves.) As good as the Scurion might be, I still insist on having two sources of light permanently mounted on my helmet.
Does this light have a magnetic switch (please say no!)? How does it compare to the Scurion in terms of space required on the helmet?