you have to get used to getting the water out of the sponges, keep trying but only use on the bigger stuff, splashbacks are always better with the old method of sponge hands bucket..
the sponges that come with the Karl Dahm are really good just throw your utility knife around the sponge (new blade) not to deep just enough say 3mm..that should help grab more grout.rinse i always do more than two go's over the rollers and tilt back so the ends wring out.