Bottom Bracket cable guide

Am in the final throes of building up a road bike and went to fit the gear cables last night, only to discover that the rear mech's cable has frayed and upon cutting it, realised it was too short 
However in looking at the route, it seems the cable guide is made from Stainless Steel, which seems odd to me and a potential bind for the cable once some gunk gets in there.
I've ordered a replacement plastic unit but was wondering whether this was a standard feature of a Trek bike?

However in looking at the route, it seems the cable guide is made from Stainless Steel, which seems odd to me and a potential bind for the cable once some gunk gets in there.
I've ordered a replacement plastic unit but was wondering whether this was a standard feature of a Trek bike?
0
Posts
Plasic does a perfectly good job...stick to it....hope it hasn't cost too much, I've got a stack spare I could have flogged you!
retired 9.6kg Carrera Kraken
The Carrera Hardtail combined thread - come on all you Carrera's!
The Sons Scott Genius RC20 build
99 pence from CRC
Everyday Commuter
retired 9.6kg Carrera Kraken
The Carrera Hardtail combined thread - come on all you Carrera's!
The Sons Scott Genius RC20 build
He's probably bought a bike as well to get free postage.
busted
Everyday Commuter