These strings are really awesome!  The pure nickel wrap has much mellower and richer tone than nickel-plated steel.  I like them on humbucker guitars - I have a 1989 Paul Reed Smith Signature guitar which these suit perfectly.  I like D'Addario XL110s on Strats and Musicman guitars, but on the PRS, the XL110s sound thin compared to the Gibsons (interestingly, both sets sound about the same on a Strat).  The only downsides are that they cost more and don't last very long compared to D'Addarios.  If you have a PRS or Les Paul, you owe it to yourself to try a set of these out - you won't be disappointed.  The feel of the Gibsons is much nicer than the pure-nickel Ernie Ball or Fender strings and the sound is better too.