I don't understand why you would need a fixed AND a slider handheld. We have a Grohe slider with a handheld. The head is a Relexa and the bar is something else, but they are interchangeable with Grohe. You can slide that sucker way up with just a touch and easily tilt it up and down to any angle. Then it lifts right out very easily to spray those other parts that down falling water misses. This is very, very different from the (cheaper) ones that are not adjustable when you put the hand held head in it's holder, when you have to tighten a screw to keep it in a fixed place. I have arthritis in my hands and this one is very easy to operate...and it looks good too! I hope you have access to a plumbing store that has some of these types on display. Play with them and see how you like the way they adjust...they are all a bit different and I know you will find one that is just right for you. -Babka

I am in process of designing a shower with the same dimensions and questions. Same drain plan. Preliminary decision is to go with Kohler's hydrorail shower system which is exposed, includes the handheld diverter and supports a rain shower head on the 18" extension. That puts someone showering between 18-24" from the shower head wall. It leaves considerable space in back for a bench or a chair. The advantage to me is simplicity -- that system supports a single pressure balance valve and has an integral diverter. Alternately, to do a ceiling mounted rain head plus a hand held, a thermostatic valve is needed and the price escalates. For a master, I'd likely go with thermostatic. We have one in our master with a separate hand shower and it's excellent. But for this powder room bath expansion I think a single pressure balance (on/off) shower is sufficient. It's really a question of how the shower will be designed/used. I don't have experience with the hydrorail so I did do a post asking if anyone had used it.

This thread is old but maybe this comment will help someone else who has decided they want a hand held. Don't listen to the naysayers. You don't need to buy a new valve with a diverter and a cover plate. The valve that you have has 4 ports. One for hot water, one for cold and a third one goes to the shower head. The fourth, down to the tub spout would normally be capped if you don't want a tub spout. (You can go in through a wall behind the shower so that you don't destroy the tile.) Instead of capping it, sweat solder a short piece of tubing that extends off to the side. Onto this tubing, solder a brass elbow with female pipe threads (just like in the wall at the shower head). Screw into this elbow a short brass nipple that will extend through the shower wall to a nice chrome attachment mounted on the wall to which you can connect the shower hose. You'll need a diamond hole saw to cut through the tile cleanly. (Then mount the hand held anywhere you want, like in the picture.) Easy peasy. Any plumber would understand these instructions. The water will normally come out the hand held (just like with a tub spout), but by pausing the hand held, water will come out the shower head. The hose is is only under pressure when the pause function is engaged and the water is running. You'll be in the shower if it breaks.--no risk of water running during your 2 week vacation. If the hose has to be replaced in 3 or 4 years, so what? The pause function on the hand held means that the hose was designed for intermittent city water pressure. It's a Delta. The hose will be of good quality. ...Now just repair the drywall in the adjoining room.

I installed a Hansgrohe Croma 220 showerpipe in my remodeled shower in which both the shower head and hand shower are in one column. If I were to have a separate shower bar with hand shower, I'd place it next to the the valve and shower head. The diverter will still be on the wall with the faucet and shower head, I wouldn't want to have to swivel inside the shower to use the hand shower and, as your husband says, the shower bar and hand shower will stick out from the adjacent wall and get in your way.