Were they ever in favour? I know they were the go to for a lot of German cycle tourists for a number of years, but they were always a bit of a rarity in the UK. At least amongst touring cyclists, I understand they were a real boon for trials riders, but that isn't a field I know anything about. I tried them on my Raven for a short while, I didn't dislike them, but neither was I wholly impressed, the front one needed a brake booster to get the squealing down to an acceptable level and although I appreciated the light touch, and the self adjusting, I don't think they greatly improved my stopping distances. I would have stuck with them, but along came carbide rims and there was no Magura pad, so the V's went back on.
I know they have their fans and if they work for you I can see no reason not to continue with them, but for me, hydraulic discs are preferable in every way.