First I was skeptical. Long lasting tone, no stain? Its might be a fairy tale. And the price seemed high (especially in my local music store), around 2-2.5x of a set Ernie.
I gave them a shoot.
My experiences like with the new set of strings like, they lose that nice sparkling tone after one or two week and they get dull after 3-4 weeks. After month even if I clean them properly they get stained, I am not feel them smooth anymore. That bothers me, but I don't want to buy new strings every third or forth week.
I use a set Elixir for more then 2 month and they still have 80% of the tone and smoothness. Looks new, no rust so far.
Quick math: price of 2 set of strings, life of more than 4 set of strings. It saved me 50% money or more + less hassle with the string change.
Of course, it's my personal experience. I dont play too much, the humidity is low in my room, and my hands chemistry is mild.
I guess it can be even more useful for people with acidic sweat.
I'm joined the club of Elixir fans.