It sounds like most of us here are taking the same approach. We realize that there's always a way to get a bit more velocity from a given cartridge, but there's always a catch somewhere. An extra 100 fps isn't worth poor accuracy.
I see the Superformance thing as a marketing tool (and a good one) that was first aimed at non-reloaders. For a lot of folks that buy one or two boxes of rifle ammo a year, it sounds great to get an extra 100 or 200 fps. Their accuracy is a crap shoot anyway, mostly they just try various factory ammo and see what works (if they are even that thorough about it). From what I see and hear, the stores are selling Superformance factory ammo pretty well. Shoot, when I was 20-25 years old, I would have been waiting in line to get the newest fastest ammo for my 7 mm mag. So, it's only natural that they test the waters to see how many reloaders want to to try the newest miracle powder. Quite a few will probably give it a try, just because we are naturally curious. But most of us sit back and think about it and realize that even with existing powder choices, we are very rarely loading the maximum loads. We might try one during load testing, but typically we are running our rifles a bit below maximum attainable velocity because they work better that way.
Time will tell. If experienced shooters start telling me they are getting phenomenal performance, then yeah, I'll eventually buy a can of it to try out.