I'm actually curious to try those.  Do you use the Mr.Softer the same way you would MicroSol/Set?

I've had the Vallejo Decal "Fix" and "Medium" on my shelf for a while and decided to give them a serious try.  I'm still reserving judgement.  I followed the directions from Vallejo's product information page which was to use the alcohol based "Decal Medium" first, then apply decal, then finish with the "Decal Fix".   Worked well in that I got ZERO silvering, but it was imperative to finish with a coat of matt varnish to knock out the admittedly extremely slight brushstrokes left by the fax/medium.  The decals look good but the edges of the film are I think too visible at certain angles.

Confusingly there are a couple post on Vallejo's own blog which reverse the order of use which doesn't make sense to me but maybe I'll try that and see what it looks like.