Ernie Ball 3125 Extra

These strings will last you 3 months without deteriorating tone. I've compared them to their uncoated counterpart and you can't really hear much difference. After a month, however, there's a HUGE difference.

If you live in a humid environmentas I do (Azores) then these strings are a must - coated to protect, and of course will keep your strings fresher and protect under any circumstances from sweaty fingers and dirt.
Very quick settling in period, maintain brightness and relatively inexpensive. Quality and consistancy as the brand promises. I use these on half my guitars and 7's on the remainder (same brand). Never dissapoint and not had a string breakage for years.