Decided to buy this product after being very satisfied with the sister product Forever White silicone sealant.
I built my shower around 9 years ago without installing a shower extractor fan DOOOH! I used the sealant around the shower tray edge where it meets the tiles. The shower in question is used a minimum of 3 times a day and with all that moisture and damp air it doesn't take long before the dreaded brown/black mold starts to appear. I have used another brand of supposedly stay white silicone and within months it was black. A friend of mine who is in the trade gave me a tube of forever white silicone about 3 years ago and I have to say I am very impressed with it. It is as white as the day I first applied it.
I have used a grout pen (EXPENSIVE)and apart from being tricky to stay on the grout lines, I was instantly un-convinced that it would last as it only lays down a very thin layer of product, takes ages to apply and in some parts had to be re-applied a few times. Again, in a very short time it started to discolor and get moldy.
Forever White is straight forward to use, make sure the shower is completely dry, the minimum recommended time before last use is 4 hours, if you can wait overnight, even better. Unscrew the cap and lightly squeeze until you can see the product on the sponge tip, you might want to dab it a few times to get the product flowing. Continue to lightly squeeze the tube whilst applying the product in a zig zag motion across the grout line. Don't worry about the excess going over the grout lines its not a major problem. Once applied, leave it to dry for at least 4 or 5 hours.
Once the product has dried, I found it easier to climb into the shower and use the shower head with a sponge to gently wash the excess off the tiles. I will admit it does take a bit of elbow grease but don't be tempted to rush and be aggressive as you might scrub the new layer from the grout lines. Once the excess has been well dampened with warm water it starts to come away quite easily.
The end result is perfect. Its been on for months now and no sign of discoloration or mold. Brilliant.
I have only given the product 4 stars because the sponge applicator could do with being only half the size reduce the excess and the amount of elbow grease I needed to clean of the excess product but this is just nit picking as the shower looks like new and well worth the effort.
It's not often in life that the cheapest product is better than the most expensive market leading product but in this case it definitely is.