Superjens -
As you might guess, I follow several car care forums. Langka has gotten mixed reviews from what I've read. I have not tried this product myself.
I could see how it 'might' work on a single layer (clear coat) repair. If the repair calls for more than that - color coat and even primer, then I'm not so sure.
Using ultra fine sandpaper, 2000 grit class, is a well known method. Details have been posted here and on other detailing sites.
If you're not 100% comfortable with any technique, practice on a spot that is not obvious. Even on another vehicle that's around the house.
In any case, be patient, do your best and don't expect miracles.

dave and xtoy - who could use a few miracles

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