Folks, there are huge differences between ShowerGuard and Dimon Fusion -- they don't even do the same thing. Dimon Fusion is essentially just a permanent version of Rain-X and like Rain-X keeps glass from streaking, spotting up, etc. It is a coating applied to the surface of the glass and will (eventually) wear through, although I think it is debatable whether you wouldn't wind up spending more on repeated Rain-X treatments. Both keep water from pooling on the surface under tension, and thus tend to decrease the amount of soap and harmful mineral deposits that remain on the glass after the water evaporates. That mineral residue will eventually pit the glass surface and cause the permanent "clouding" of the glass that no amount of scrubbing will ever clean off. And of course, your glass will look spiffier between real cleanings with less streaking, spotting, etc. ShowerGuard is a completely different beast. First, it costs almost twice as much as Dimon Fusion and can add 25% or more to the cost of the glass. Second, it does absolutely nothing to minimize water spots, streaking, etc between cleanings. Water will pool on it just like ordinary, untreated glass leaving streaks and spots unless you squeege. BUT, glass treated with the ShowerGuard process will never pit and turn cloudy like untreated glass because the glass surface is sealed at the molecular level so the mineral deposits can't get in do their number on the glass. It is also permanent. Its really about what you want and what you want to pay -- if you don't mind the constant "wax on, wax off" then go with the Rain-X. If you want to save some elbow grease, go with the Dimon Fusion. But both leave a risk of long-term glass damage, so if avoiding that is the most important, go with ShowerGuard (although you will need to squeege or live with occasional water spots).

I still have time to change this plan, and order a marble shelf to go in. How would this be done? The bottom tiles would be set, and then the shelf gets set on the top edge of the installed tiles. The top tiles then get cut to take into account the thickness of the stone and still keep alignment with the tiles on either side, and then they get installed. As for objecting to installing on top of the tile, yes and no. ANY kind of intrusion through the tile and waterproofing is cause for concern. But that can also be alleviated if it's "corked" back up with caulking. This one below, I'm showing you the unfinished pictures so you can see how it's done with the stone sitting on the tile's edges:

I like to design my glass block walls to be build on a mini shower dam. Same finished width as the glass blocks and about 4" off the ground. We bring the shower waterproofing membrane up and over this dam and then anchor few of the reinforcing pieces into the curb and seal those penetrations with something like Kerdi Fix. I'm sure on the next glass block wall we will use some Ardex 8+9 as well. The weakest links in the design where the fasteners bite into the shower curb. Both these walls are straight with a Neo Angle barrier Free Entry. We ran the dark marble tile up the walls and clad the shower curb with it. The Glass blocks ran full height and we added a ceiling curb to allow for the difference. Worked out well - the floor curb and ceiling curb where the same! In creating the heated barrier free bathroom we raised the entire floor height. This height change corrected at the entry with a custom Oak Reducer. Roughly 1 1/4" 1 3/8" This is the guest shower in the same home. This shower we ran a straight wall and added a low curb in front. The glass blocks reinforced with mini rebar and pinned to the curb, ceiling and far wall. Curved face block used at end.

I don't. I have this one purchased at BB&B (mine isn't double). I'm pleased with the quality and didn't have to drill into the tile. The hookless shower curtain slides over it effortlessly. It hasn't budged since DH put it up in Aug. The Gripper