This is a great product. The design is as you would expect, but the handle is extremely sturdy and I was surprised to see that they even provide a spare blade. Tested the product on our tiles and it works brilliantly. 5 out of 5.
Horrible and time-consuming job but a great little tool if you intend to do it manually. I cleared out quite a lot of grout with this, and the original blade is still going. The device is also supplied with a spare blade. If you take your time, the risk of damage to a tile is slight. I suffered one very small chip that was hidden by the grout. If you intend to clean the grout out of an entire shower enclosure, etc., then buy/hire a dedicated power tool (or employ someone who already has one).