Hi, we just went through this ordeal for my son's bathroom covered with white subway tiles. After sifting through many pictures, my heart was set on Mapei's Frost - even though my contractor insisted on white. Unfortunately, Frost was not readily available since it's considered a special order color at Lowes and HD. My contractor suggested Warm Gray and mocked up a couple of tiles. For me, it was way too dark. Luckily, we called around a found a store 20 miles away that had 2 bags left. (Floor & Decor). We went with Frost and it looks gorgeous...even my contractor had to agree. I'll try to post pics later. Good luck!

We used Mapei Flexicolor in our kids' bath and like it so far. It's a medium gray (can't remember the color), but it very consistent in color. We are using Latecrete in our shower. I think we have Sterling Sliver (Can't remember for sure). I've used their epoxy grout before & loved the performance.

Bill, I am reading many comments that epoxy grout will yellow over time because of UV rays. Would this only happen if direct sunlight hits it or after long term exposure to any up light, even if filtered. Would Mapei‘s Flexcolor which is an acrylic grout have the same issue?

We spoke to the manufacturer and they basically said that this happens and it is the nature of the product. That said, the likely cause was the contractor mixing the new bag I bought with an old bag he had. TEC advised not to use old product or bags that have been open for any length of time. They did suggest using distilled water instead of tap water, but I doubt that was the issue. I made sample boards with tap water and didn’t have any discoloration issues. TEC sent me their grout colorant and I applied 2 coats. This was very tedious and took at least 5 hours for a small powder room to paint every grout line with a tiny brush. However, it did work and nicely covered up the white spots. You can see the painted colorant on the first pic and the pic with the toilet is before the colorant (notice all the white spots). I was very irritated and stressed by all of this, but was relieved the colorant worked and it didn’t have to be retiled.