Another satisfied customer... have used Elixirs nano lights ever since a music-shop guy in Melbourne, Australia recommended them about three years ago. I put them on my Tanglewood, then later on (for unrelated reasons) bought a ColeClark FL2AC which came with them as standard. Both are 6-strings and are kept in standard, concert-pitch tunings. I occasionally use drop D and open tunings, retuning on the fly, and the strings seem to cope with this just fine.

Never had a breakage, strings always sound nice and mellow and while dullness can creep in, this happens over a period of months (and my guitars get well used). Previously I used Martins and string sound quality seemed to go off much more quickly.

I used to keep my Sigma 12 on Martins, but at the last re-string changed it to Elixirs.

Also agree with posts above that Elixirs (and, I suppose other brands of coated strings) reduce squeaks when changing chords, which is always good.