I have been taking notes to see whether or not the glue treatment removes anything else on average soiled 99cent vinyl.
I am happy to report that simply scrubbing with a paint pad + dawn, covering labels with dent pullers, rinsing, perhaps a spin thru the spin clean, and finally using a homemade shopvac to lift the water off, is usually going to get about, oh, 95% of the noise and crud.
I've glued several lately, and only heard a SLIGHT improvement over these methods.
HOWEVER, I've also seen the glue method actually improve scratches, due to lifting the edge of the scratched wax. Only happens occasionally, but it has happened.