Have used TEC bright white grout (regular and XT) in bathrooms and on our kitchen backsplash--none have yellowed.

Hi cat_mom - thanks for the response. How long ago did you use it? Did you use it with white glossy subway tiles by chance?

We used tec power grout un sanded dove gray on glossy white subways,. No issues yet. No scratching.

We used maipei white grout on our previous shower and it took about 5 years to start yellowing, but that was with sub-optimal cleaning and hard water.

Guest bathroom shower surround, glossy white tiles, "regular" TEC grout, 2008 I think.

MB and hall bathroom tub surrounds, glossy white tiles, TEC XT grout, 2011.

No issues. The XT grout doesn't require sealing, but can be, using a solvent based sealer. We have moderately hard water. We wipe down the tub surrounds with a microfiber cloth after showering (to prevent water spots on the glossy tile). I clean the bathrooms pretty much weekly. I spray the tub surrounds with 7th Generation disinfecting bathroom cleaner spray. Let sit a few minutes, and wipe dry with a microfiber cloth. Tile and grout look as they did when first installed.

Thanks everyone. I'll be using TEC's sterling, which is a very light grey in our kitchen with 3x6 white subway tiles. For the bathroom, I'm still undecided. Since our reno has been delayed so much, I won't be able to do the kitchen first, so at least I can see what it will look like :(

I have white tiles with white grout now, but they're about 20 years old and looking very yellowy, so that's a given.

I've had to make so many decisions with this kitchen/bath reno that I think my head is going to explode!