A colleague of mine turned me on to these, and in particular to this strange gauge of 9.5 - 44.
I had struggled in the past with standard 9s on a guitar with high output pickups and a warble-happy whammy bar.
I find these strings to handle really nicely, a perfect amount of slick and grip (finger contact) and they positively scream in my current configuration. I've put them on a guitar that I don't play live often, and I find that the strings don't deteriorate over time with the guitar being left in the case.
This is very subjective and a question of personal chemistry. I mean, I've seen players go through a pack of the best "long-lasting" string on the market in one night, so it'll always come down to which material lends itself to your handling.
Despite the price tag, I am not sorry that I've purchased those, and I just picked up a few more packs to tide me over the months of session work.