I started out playing on Martin Marquis when I was in high school back in the seventies. I guess I have never bought any other brand of guitar strings to this day. I switched to SP phosphor bronze a while back and have really liked them. I have yet to try Lifespans but I think I will buy some and see how they sound. I had always played lights until I bought my Taylor, which I strung with mediums. They took a toll on my fingers at the beginning, but the sound is really great.
Gittar Strings
I have tried every string out there and have stacks of packs I don’t use anymore. Tried going back to the cheaper strings recently and after a year or more of using coated Elixer poly webs it hurts…lots of string finger noise and just didn’t enjoy them. Tried the Nano web and they are Crap, but the original Poly webs hold up sound good and last a good while. I use heavy picks and the nano webs wear out in about a day or two. The Martins are ok to, but still prefer the 12/54 Poly Web.
— Begin quote from "Jerry M"
I use heavy picks and the nano webs wear out in about a day or two.
— End quote
Doh! 
Thanks for saving me from trying those out.
I have used both the elixir and the Martins and I have a set of elixirs on the guitar now and to tell you the truth I prefer the Martin XP mediums they last as long and the have a special tone to them that the elixir does not have after about a week they are sort of bland . but from now on I will use Martin strings they have the best sound for me . and they last just as long if not longer than the Elixir strings. I like the color of the B and E string also they are a brass colored string and it just makes the guitar look much more mellow also . Tone is like beauty is to the eye it is to the ear of the beholder . The next set will be Martin meds and I will stay with them . The 56 on top makes for a mean bass and the E string on the bottom is thick enough you can strike very hard and it still sounds great.
I have noticed a big advantage to coated strings is the non coated hurt the fingers of older folks so when I change next time it will be life span lights . the older we get the more we hurt LOL Most of the coated strings I have used I was satisfied with .
I just put a set of D’Addario the EXP’s on my Martin today Aug the 9th 2014 and I have played them for about twenty minutes and like what I hear . the feeling under the fourth string as I slide leaves a tingle on my noting finger but no sound can I hear . I have tried the Elixirs but found I like the Martin better but the last set I bought went dead in about three weeks .so I sent for the D’Addario strings, light gauge and like them . The bottom E string amplifies better with these . I was taken aback when I read on the package this string was red and this one black and so on thinking oh no these are colored strings ., The ends are colored to tell them apart . no big deal LOL . I think these will be keepers and I will use them for awhile .