"As a DIYer I have not grouted tiles for many years. My task - 2m high wall surrounding the bottom, side length and tap end of a bath to allow its use with a shower. All grouted in under an hour! You can also clear off the excess as you go so very little need to clean up afterwards. Watch some videos of how to use a grout float. Money well spent."
"First time of using one of these, and I must say it made the job easier. I grouted a 15m squared floor in an hour. As long as you keep it at 45 degrees like plastering and the grout not to thick job done."