Passport still valid for 13 months. Buddy tells me that I should apply for a new one now. As far as I know there is a minimum requirement of 6 months before expiration in effect for neighboring countries as far as border-crossings, and visa-stuff is concerned.

So I just wonder, what bnefits there could possibly be, if I already get a new passport now?

Cheers.

The only reason to do it now would be if you were to apply for a multiple entry non immigrant visa. They often want 18 months validity to issue those.

The recommended renewal application date is 9 months according to UK and US governments.

The UK even gives you the 9 months back by adding them to the new passport.