I have bought both products before and each has its pros and cons. Let me try to break it down for the benefit of all future readers.
Grout Shield
Pros:
1. Easy to apply, drip 3 small drops with good spacing along grout line. Then use a thin paintbrush to paint it along the grout line.
2. Beautiful colours for the first few weeks, but it will darken over time.
3. Waterproof, protects your grout from water damage/corrosion.
4. Doesn't dry up in the bottle if kept properly, I can still use it after 2 years of storage.
5. If your existing grout is dirty or flush, you can still apply it, you have to use a scraper to careful scrape along the tile line for it to look good.
Cons:
1. Very expensive, but I can shield my whole floor area with less than 1 bottle.
2. If used on flush grout, try to use a slightly damp cloth or tissue paper to wipe off excess on the tiles quickly, otherwise when it dries, its harder to remove.
3. If used on sunken grout, it is easier to scrape off using a good scraping tool after it has dried. But don't wait too long before it becomes too hard to remove!
4. If your tile is porous/matt/rough/non-glazed, it will be extremely hard to wipe it off after its has dried. This will leave the grout lines looking very messy. If you are a perfectionist like me, do not ask your maid to do for you as she will likely make it more ugly due to slip-shod work.
5. Although it's quite hard, but it will still wear and tear after time. I had to redo some areas after 2 years. And due to its colour darkening with time, I ended up with different colours along different grout lines, which is quite ugly.
6. After grout-shielding, the area cannot be scrubbed with hard brush anymore, otherwise the coating will come off. You have to use mould remover spray in toilet areas if you need to clean it.
Davco Rejuvenation Grout
Pros
1. It is some kind of latex/rubbery substance that is supposedly waterproof and mould proof. So it can be used in toilets, balconies, etc.
2. It can be used on wall grout joints that have become loose and provides a filler material for the joint.
3. It can be used on porous/matt/rough/non-glazed tiles, as its softer and easier to remove excess on tiles surface than Grout Shield.
4. Colour stays the same (so far after 2 months).
5. Much cheaper than Grout Shield.
Cons
1. It is a paste like substance like putty. So its much more difficult to use on flush grout lines. You can only use it on sunken grout lines.
2. Its much harder to work with than Grout Shield, as you will need a grout float for shaping, etc.
3. After drying, it will shrink, so be prepared for your grout line to be sunken in, no more flush grout.
4. Somehow, it does not create a smooth surface like normal grout powder, the surface is a bit rough like sandpaper and when you press it hard enough, it will sink in.
5. I tried in my shower area, certain areas still turn black or mouldy, so I still have doubts on whether it is really mould resistant. But, I applied Grout shield on top of the black areas, and they become beautiful again.
In conclusion, both products has its pros and cons. Depending on your area of use and needs, you have to trial and error. I will be trying Aqua Mix Grout Sealer next.
