No experience with the shower tornado, but I'd love to hear the reviews too. We do have a walk-in, door-less shower with a bench and I don't find it to be cold--& I am almost always cold anywhere else! Our shower is ~4'x7'. The entry is on the short end with the bench on the short end opposite the door. The shower head and handheld shower are placed on one of the long walls side by side. Our builder swore we would have 2 things happen--the shower would be cold and we would have water splash out onto the bathroom floor. He pushed us to install a heater over the shower, but we chose wait and see what we thought after we had actually tried it out. So far, neither of us are cold in the shower and we haven't had any issues with the water splashing out. We have an overhead rainshower, but we hardly ever use it. Here's a pic of our shower: If you're thinking about planning for the possibility of needing a fully handicapped accessible shower you will need to plan for at least a shower thats 5'x5' to allow for a wheelchair to turn around in. This is what my parents have for just that purpose--their shower is 5'x6' with a 3.5' entry on the 5' side. I've used their shower before and it doesn't get cold either. I will say, our seat could have been deeper--its only 12" deep. 16"-18" would have been more ideal. Another thought is to not do a built in seat, but have a removable stool/seat/bench--plenty of threads on GW on the pros & cons of each seat option. As far as storage, the answer is niches built in to the shower wall. They are built-in so they don't protrude into the showering space and offer a myriad of options as far as how to set them up (i.e. shelves or no shelves, tall & skinny, short & wide, double decker or single decker, etc). If you look close in the shower pic, you can just make out the little ledge where our niche is and a sliver of an orange shampoo bottle just in front of the 1st shower head and shower controls. Hope this helps!

6" is probably most common because of accessibility and price. It is by no means standard though. I've done them with 3", 4" 5" and 6" as well as LED panels. With a 66" long shower I'd have put in 2 @ 4" dia. but that is me. If it has enough light to do your business in there, then I wouldn't worry about it.

If it were me, the option I prefer is no window. Windows in showers are often problematic, and can result in leaks over time. If you really insist on having natural light, can you put in a skylight instead?

Wow thanks for all the input. My wife will use the tub if we have one. I'll have to look into an air tub. The shower and tub were drawn at 6' but could be changed. I'll look into 5.5' tub to see if she will fit. We weren't planning to do a shower seat at the far end from the shower head because we figured 6' would be too far away. I like the idea to use a curtain now and glass door later if we want. I can't move the wall by the double sink because there's another bathroom on the other side of it. The wall the double sink is on is only 4.5', I'll look into a trough too.