Guitar strings. The topic alone strikes emotions and uneasiness. So what do I have to say? Strings are cheap, and strings are cheap. Wait... did I say that twice? It would appear that I did. So lets say it one more time, Strings are cheap.
Now that we have established that strings are cheap (I usually purchase mine online in bulk), the discussion can commence.
When somebody asks me what strings I use, I tell them.
When somebody asks what strings I recommend, I ask them this: "What strings are you using now? What do you like/dislike about them?" That is all I can say. Strings are a personal item that is largely preference.
The most common issue is NOT breakage, but we will cover breakage first. Seemingly like the string is bad, right? Not all the time!
I say this because if you keep breaking strings in the same spot, you probably have a burr. Not to worry though, they are easy to smooth out a little bit with a little bit of sandpaper (very fine). Once you get that spot fixed, you shouldn't have a problem area any more.
Typically strings break at the bridge/saddle, nut, or tuning keys. Unknown to you, what is happening is that a burr is developing in a problem area. Your string is slowly getting weaker and weaker as the burr is cutting deeper and deeper into the string. You will be
[Actually I most commonly break strings bending, but that is a personal thing.]
The most common issue that strings come up 'short' on is the aging (oxidation?). New strings sound jangley and bright and lively, after a little while they lose their luster. Then they start to sound muddy and dark and DULL sounding. No bueno in my book. String life has a million variables, from the sweat and acidity of your sweat on the strings, to the climate. Some people have much better experience with certain string brands than others, largely due to the different metals/coatings interacting with their body.
You can research the different
There are products that claim to enhance string life, I call it snake-oil. Some swear by it, I don't. You can decide for yourself.
In summation: Strings are cheap, play the field.
Keep on reading, and I will keep on bitching.