Looking at linear comps for a 458 socom carbine/ rifle build - have a barrel already, going to go with a Tromix bolt (keep waiting for them to go on sale, don't think its going to happen), and wondering about a linear compensator for the build.

Kaw Valley offers a 2.25" and a 3.5" - any real difference in performance anyone knows of?

Other options folks have used?

I've only ever used the one Tromix sells but have been very happy with it

ETA mines a radial not a linear

@TonyRumore

I've never seen a Kaw unit first hand, but it would appear the main difference is the Tromix 2-piece design versus the monolithic design of the Kaw.....which of course makes the Kaw cheaper to produce.
However, I imagine the functionality is about the same.

The Tromix 2-piece design allows us to stock the rear ends in various thread pitches and the front ends in various exit holes, that way we can mix and match the two in order to get whatever thread pitch and caliber combination the customer might need.  We can assemble about 900 different combinations considering we also have black, stainless, and two-tone.  For example, we can quickly assemble a 3/4-24 22 caliber device for a big bull barrel if need be.  

Tony Rumore
Tromix

I've run the standard sized KVP on several things, including a 450BM.
Makes a noticeable difference in blast.