Just to close the loop on this thread: I ended up using Aqua Mix Grout Colorant to paint the grout a darker color to match the tile. The photo shows before and after: at bottom is how the grout initially came out (too light) and then the top is painted with the grout colorant (the uniform look I wanted). They sell colors to match grout colors from several different manufacturers; we ended up with a Maipei color that seemed to be the closest match. The application was straightforward but very time-consuming and tedious; I used a toothbrush to paint it on and rub it in. You have to be careful to not let it sit too long before removing the excess or it's a real pain to get it off the tile. But, once I had a good system going it was easy, if mind-numbing, work. I also used painter's tape to mask off the baseboards (visible in photo). It's now been several months and it has held up to foot traffic and my steam mop. We have extra in case it does ever need to be reapplied. I was very glad to find this solution as there was no way our contractor was going to agree to remove and re-grout. Anyway, I really recommend Aqua Mix's grout colorant (epoxy-based); their customer service was very helpful too. I had to buy online from stonetooling.com as I couldn't find a local retailer who would sell to homeowners directly. Also good experience with that online retailer.

Good question. it's a new product that really hasn't been around very long. Matter of fact, I'll be going to a seminar on it in a few weeks. I'll let you all know what I find out. The closest I've seen to stain free grouts is Laticrete's Spectralock Pro. There's also another one that's just recently been re-released after working out some of the "bugs" called Prism from Custom building Products. Personally, unless you're using a light grout in high traffic areas (which is going to show dirt a WHOLE lot more than it would otherwise), using a chemical grout like Spectralock or Prism is overkill in a residential setting.

Grout stain is available through most grout manufacturers. Contact them directly for information. Test on a mock up or under the stove, fridge, in closet. Do not seal as suggested in the link provided above. If color staining is a option you are considering. Applying sealer now could become a issue with staining.

it's the perfect grout color. Don't even worry about changing it. make sure your guy knows how to do this grout properly. Grout small sections, and clean up quickly (within 10 mins or so) advise him to use very little water on the sponge. Normally you would spread your grout out in large sections while using the float to press it in the joints, and then go back and wipe up. sometimes as long as 30 mins. You can't do that w/this grout. (if he does large sections and waits to wipe like on normal grout, the grout leaves a filmy residue that takes hours to clean off!. Ask me how I know this. I advised my tile guy how to use it and he didn't listen to me. I spent 2 hours using another product to remove the grout residue from my marble tile. ) FlexColor CQ has a stain resistant property in the grout, so you shouldn't have too much of a hard time cleaning. I have it in my shower.