I had to jump up and down to get unsanded grout. From the get-go I told everyone from the person bidding on the job to the guys doing the work that I wanted unsanded. Then they went ahead and used sanded because a sample board I had done for color was sanded. I could only get small bags of grout in the color I wanted to test in sanded. He said, "Oh, that's what I thought you wanted." As it turned out, I had chosen the wrong color for the grout and had them remove it 10 minutes after it went in. The next time they used unsanded. It looks SO much better.

Bill Vincent (the GW tile guru) says in the FAQ on tiling that the answer to sanded vs. unsanded is simple: If the grout line is LESS than 1/8 inch, use unsanded. If the grout line is 1/8 inch or more, use sanded.

but I do know that sanded is much stronger and hold up better. I think it is intended for 1/8" or wider grout lines. It's not that it's stronger. It's that it doesn't shrink as much, because of the fact that most of its bulk is the sand. As for the explanation of the different grouts, I just posted this in an FAQ thread on the gallery side of the bathrooms forum. Here it is, copied and pasted: Although there are others, for all intents and purposes, there are two kinds of grout-- portland cement based, and epoxy. The portland cement based grouts are the conventional grouts that have been around for millenniums. Although in the last few decades, they've been modified with latex and other polymers to make them stronger and more resistant to mold and mildew, they're basically the very same grouts that have been used since Greek and Roman days. There are two kinds of portland cement based grouts. One is sanded, and the other unsanded. The only difference between the two is, as their names imply, the sand. The ONLY thing that determines which grout should be used is the joint size. NOT the glaze, NOT aesthetics, NOT the material (ceramic vs. glass or polished marble), NONE of those. I'll repeat-- the ONLY thing that determines which is used, is the joint size. Anything under an 1/8" takes unsanded grout. Anything 1/8" or bigger, you use sanded grout. If you use unsanded grout in larger joints, the cement in the grout will shrink way too much as the water evaporates out of it, and the joints will end up shrinking and cracking bigtime. If you try using sanded grout in smaller joints, the grains of sand will literally clog the top of the joint, and not allow the grout to get down INTO the joint, and the grout will flake off in a matter of days. As for the Epoxy, most epoxy grouts use a much finer "sand", and therefore can be used in any size grout joint. Further, epoxy grouts are everything people say they are. They're much easier to clean, practically stainproof, and also extremely expensive. Most epoxies will cost atleast 4 times the cost of conventional grouts, and the installer will also usually charge a premium of between 1.50- 2.50 a foot for the use of epoxy grout. There are alot of people who will disagree with me, but my own opinion is that for most residential installations, epoxy grout is bigtime overkill. The ONLY times I'll recommend epoxy grout is first, if you're installing a tile countertop, and two, if you have animals in the house that either aren't housebroken, or are prone to accidents. In either of those cases, epoxy might be worth the money. For anything else, though, conventional grout is more than good enough.

Actually, You'd be better off with the sanded caulk. I said what I said above more for the benefit of others who may go looking for unsanded caulking in the future and read this thread. The same rule oif thumb about when to use sanded and unsanded grout does NOT allpy to caulking. ALthough you CAN use an unsanded caulking if you wish, the whole point to having the two types of caulk is to match the grout as closely as possible, and the sanded caulking, in this case, would do a better job of that. I'd stick with what you have.