I don't often get to use Ardex grouts,but I do seem to remember using some Ardex FL a few years ago that sat in the joints well and wasn't a nightmare to clean off the tiles. Depends on the tile and ambient temperature as well mind you.
My tile guy has the grout very low between the rectifies tiles so you feel the sharp edges. Its a new shower that was just put in and not used yet. Can I put more gout to make it flush as I don’t want to cut my feet?