1. How well does it hold up in a shower? I would not worry about soap hurting the CS. The main problem in a shower will happen on the floor due to moisture from the pan. Every shower is different.
2. Can you use it on unsanded grout? Yes - but the problem with unsanded grout is not the grout but the install. Oftentimes, with unsanded grout the grout is recessed less and more even with the tile. This is what creates most problems CS unsanded grout.
3. What exactly is the CS? Some are epoxy and some acrylic - depends on your preference.
4. Life expectancy? Most off the self products will not hurt CS. A customer would have to try really hard to remove the CS and use a commercial grade stripper or coating remover to effect it. I normally recomend neutral cleaner.
5. Life expectancy if cleaned with neutral cleaner? It is difficult to put a time frame that applies to all situations. Factors that effect the life are: traffic, method of maintenance, commercial, residential, etc. When people ask how long will the product last, they are really asking how long will the floor look clean. That depends on them. I always tell them that I guarantee that our product will not chip, flake, or peal and that the grout will be no longer porous: therefore, easy to maintain. I have seen floors that look good for 8 years and others that need to be cleaned after 1 year.
6. What else should I know about CS? The best way to sell CS is to do a demo - we always do a demo and over 75% of our jobs turn into CS. We are not aggressive, we simply show them the options and explain the pros/cons. Nothing will give you a better before/after result and nothing will provide better protection. If you can convey this message it is an easy sale.
A good way to address the question - "how long will it last" is with all factors being equal -colorseal will outlast any clear seal by 10xs and your floor will look new upon completion. We call the first treatment an Initial Restoration and any future services you can customize a maintenance program that meets their needs. This also justifies more money for the initial restoration. Once that is complete the floor will be very easy to maintain. This is a great customer retention tool for carpet cleaners. Every year you can rinse and extract the floor since you are carpet cleaning in the house.