I keep ruining my rear mech outer and blame the big curl of cable before it goes into the rear mech. My mates SRAM goes in nice and straight and he never has any fraying outer issues.

As I don't want new shifters etc, which shimano rear mech has the straightest cable entry.

If anyone has pics it would be good too.

see if you can get your hands on one of these . . .

. . . not that easy to come by these days but will do the job and save you having to buy a new mech.

i've been using one for years – really good bit of kit.

google – avid rollamajig

SLX!

yeah, go SLX
rollamajig's aren't that great

HAHAHA I was just working on this problem myself yesterday. I've had a few rollamajig things and had them repeatedly snap at the shaft location, gave up. Instead I use the noodle from a V brake, tweaked round a little and made to fit the (subsequently shortened) cable outer. This makes all the motion of a shift occur in the relatively straight seatstay-contacting part of the outer. Works a treat, had it on 3 bikes now.

FWIW, I use an Avid Rollamajig and never had any probs with it in over 6 years.
It'll be made redundant when I eventually replace my short cage, road rear mech for a Saint m810 😛