The one thing I notice about Step Steel (had it in the 6.5 Supreme MX3s my son just outgrew) is that it is MUCH more resilient and needs fewer sharpenings...once you get it sharp anyway. It does seem to take a few more passes to achieve good clean edges if they're torn up because the steel seems to be harder. In the end, that all balances out. If I didn't have 2 sets of LS3 steel with this current pair, I'd have switched him out.
Overall, I'm sure I'm well in the hole with the purchase of the sharpener and quite a few different rings until we found what all 4 of us like (my wife and I both play hockey too), but I wouldn't go back to a LHS here in Dallas unless my son ended up playing at a the one rink where we have a trustworthy sharpener. The fact that I can throw the skates on the sharpener and trust the machine implicitly to get them right while I tape a stick or pack a bag is the ultimate in hockey parent convenience. I guess if I included gas and time spent, I might get close to break even in another year or 2 in a pure dollars sense, but this is a luxury well worth the capital costs in my opinion.