I haven't changed my strings in 5 months. The strings are kind of getting out of tune when i bend. Other than tuning stability what are benefits of new strings?
This is completely subjective - there is no right answer.

Personally, for me, I love old strings because they sound amazing to me. I can't stand that tinny "new string" sound. I can never get enough of that perfect balance, after they are broken in, and before they start losing life/ sounding dull. Old strings also feel much better to me (read: old meaning worn in, not rusty/black/utterly disgusting).

I always change strings if they start to lose their tuning stability though. That's just a no-go.
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Last edited by Offworld92 at Jul 1, 2011,
New strings offer a more crisp clear sound than having old strings on, I.E. notes ring chimey or brighter. I usually just change my strings out if one breaks, my theory if one breaks another one is about to also.
New strings are basically better in every way, in my opinion. I love that tin-like sound that allows me to sound more like Justin Chancellor from Tool (when I EQ right lol). Plus, as you said, they won't go out of tune or break. I broke my bass's low E one time in the middle of playing for a winter church retreat because I had left it on there so long it finally couldn't take my aggressive playing style anymore.

And, if you are worried about it at all, new strings make your instrument look better too :P

However, like Offworld92 said, some people might like that duller, warmer sound that comes out of old strings. But personally I hate how flat everything starts to sound once the strings age far enough. The tone will REALLY suffer after a while. So, if you want your instrument to sound full and have a nice tone, you'll have to change out those strings once the sound starts going flat.
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I like to Change strings on my electrics only when they start to lose tuning stability! But that doesn't happen too often! On my acoustic guitars I love the sound of the strings as they age!
If you keep the strings clean they seam to last quite a long time! Just my 2 cents!

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Old strings...

Sound dull and flat
Are dirty and make your hands smell
Are dirty and make your fretboard dirty
Are more prone to breaking.
Are more likely to go out of tune.
Can possibly develop intonation issues.

New strings don't do those things.
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New strings are shiny. Thats enough of a reason for me to change strings.
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This one hasn't been said befor: new strings = richer harmonics
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