Fusion will work for grout joints 1/16 to 1/2”. I use quite often and is very consistent when you follow manufacturers instructions.

Pre-sealing is fine to do and should make clean up easier on the textured tile.

So, Fusion/Flex CQ type even best for pans too ahh? Will it scratch marble hex tile? What about the "hubby opps" when he messed up tile sheet when i was not looking and now three 2"hex tiles on floor near touch compared to rest being consistent 1/8"? Glad it t was last corner sheet and not in middle of floor! Bit nervous cause I am old school and used to mixing grout and how it feels. So the cementitious grouts are totally out now? Does fusion look/feel the same? Sealing floor tile or grout release? It is not real slate...just a look a like.

Shoot just read this as well from Fusion Pro "Not for use over concrete slabs with high moisture emission rates" My bathroom is in a higher end finished basement. It is on a basement pour, which then had concrete leveler added about a year ago for very minor slope correction. No cracks in flooring anywhere or what seems moisture, although full basement with dehumidifier that does collect. Does this effect things?

Well if it’s a shower pan.... you should have some sort of waterproofing system or traditional pan liner installed so I would think it’s not set directly on the concrete slab. I wouldn’t think that disclaimer would apply. You would have to test for moisture content if you are worried about it

Fusion has fine aggregate in it but generally doesn’t scratch most tiles, but when in doubt do a test sample of some scrap tile to see if it will scratch.

Fusion on is pretty DIY user friendly. I have only used Flex CQ once so don’t have much useful input about that.

The methods you use to to grout with Fusion are slightly different than tradtional cement based grout....I.e you are wiping of fusion almost immediately whereas you wait A little longer for Cement based grout. Both can look good with small grout joints an 1/8” or less. You have to be careful to use minimal water with Fusion especially or the joints can get a little more washed out.

You prob want to preseason the marble and or do a test grout sample with some scrap to see if you like the finished product

By the way, I mostly use epoxy grout (custom ceg-lite) for most of my shower pans as it is more durable in my opinion. The only time I may not choose to do this is when it’s a natural stone and there is a possibility of staining with the epoxy resins,... Then if I were to choose cement based grout I like Custom Prism. It’s color consistent and sets fast. Mapei has great products too...I typically use Custom brand because the DalTile near me stocks this brand. So I have more use with Custom brand and can speak to the performance of those products.

Yes, my shower was totally waterproofed with Kerdi and has a Kerdi waterproofed pan as well. However the main bathroom floor to be tiled will be upon basement concrete which was then floated over with self leveling because of tiny slope correction. The main floor is solid and smooth, yet is still concrete in a basement, which now makes one think of moisture issues with single component warnings.. The marble on floor in shower floor is natural stone. Ahhh now I am reading on John Bridge issues with Fusion and FlexCQ. So issues with Power Grout and this as well. Can there not be a sure proof grout that stays strong, cures perfect, color perfect and user friendly! I have fine experience, yet have also witnessed bad outcomes.

Is Laticrete Permacolor like Tec Powergrout and Mapei Ultracolor FA? What is difference? I heard that Permacolor now has a unsanded version. So, if all the issues being seen with Tec Powergrout (curing) and if is same as others mentioned, would it be likely the curing issues seen in Powergrout might also be seen in these others? I don't know if we have Laticrete Permacolor around here? Now with noticing that my subway tile may actually be 1/16 at best, but maybe even less, I guess I should go for something with no sand/aggregate regardless of aggregate size to be safe? Dang, I have too many issues....Marble hex tile has tiny spot 3 hex tiles not but 1/16, subway tile tiny grout line, floor tile on concrete and very rough grabbing texture. Just give me something that cures and stay gray and I will just not use the dang shower haha

shift your focus to "how to use" products properly and directly from the manufacturer. 90% of the drama you are getting caught up in is installer error.

Easy on the internet now.

Yes, that is so very true. However, getting insight on best products for certain circumstances can save a person from terrible outcomes. With many products out, it would be good to learn from others that have used on over 100's of jobs what there findings are before you do. I have a few situations that are not straight forward (joint sizing issues, floor on concrete (pulling up efflorescence or moisture) and very rough gritty floor tile. I appreciate the input and opinions greatly.

Perhaps a different approach to put your mind at ease. Call the tech dept, at the grout manufacturers you are considering. Explain your requirements and concerns. They will recommend which of their products will fit your needs.

TFW is spot on with his comment.

Thinking of going Permacolor Select. Questions are now if should be Select or Unsanded version. Because you can see in pics above I have 3 floor tiles that are about 1/32 (hubby touched). The rest of the hex marble floor tile are solid 1/8" with even some hair over. The shower walls are between 1/32 and 1/16 (see pics) because spacer goes in flush with 1/32 but only surface in with 1/16. The subway had built in spacer plus I added 1/32 spacer. So, to go Permacolor Select on shower walls or Perma unsanded? To use Permacolor Select on floor or will have a issue with that on my 3 problems tiles? THANK YOU GUYS@

Anyone use Permacolor Select on very small joints? How did that work out?