This linkage update is for the pre-2006 Subaru 5MT that DO NOT have the external return spring. Subaru stopped using the external return spring sometime in 1998. If you are unsure please look at your linkage under the car to check.
What it does: Eliminates much of the side to side slop that develops in the lever due to the stock bushings wearing out.
Why buy a whole linkage when the other styles we offer are just bushings: The STi, the 05+ Legacy 5MT, and ALL the 06+ Subaru 5MTs have a linkage that you can completely take apart and replace the bushings. The cars prior to this in the 1998 to 2005 timeframe have a linkage that is riveted together and cannot be serviced or upgraded.
What about the bushings - won't they just fail again? No. As part of the updated linkage you get TiC linkage bushings. They are much stiffer and more wear resistant than the stock pieces.
Why you want it: Better definition of each gear so you're no longer rowing in pudding.