I found several forums online where plumbers recommend this type of bath spout from Delta, and even this particular model of spout, for installation as a replacement. We had 15 year old builder-grade spouts with pull-up diverters that were getting so old, scaled up and sticky that it was almost impossible to move the diverter; you'd have to pull up and stick a finger into the spout and push from the bottom at the same time. It was most definitely time for a change. The Delta system involves a brass coupling that can either screw on to a threaded nipple close to the wall, or be soldered onto 1/2 inch copper pipe. Our existing spouts had 1/2" copper with a threaded coupler soldered on the end. However, the threads were too far from the wall to screw on the supplied adapter. I unsoldered the threaded coupler, cleaned up the pipe coming from the wall, slid on the Delta coupler and soldered it in place (it's a pretty substantial piece of metal, so unless you're an expert a soldering pipe I'd recommend using "tinning flux" and a MAPP gas torch to make it easier). Unlike a direct spin-on spout, the distance from the wall to the back of the Delta coupler isn't critical... anything from 1/2" to 5/4" from the wall to the back of the coupler is fine. I then cut off the extra copper pipe past the end of the adapter, put the o-ring back on with a little bit of grease to help it seal, and spun on the spout. You have a lot of adjustability, and can just spin the spout on until it contacts against the wall. After caulking around the base of the spout and letting it dry, I tried it out. The diverter pulls down easily, and seals perfectly (no leaking water out of the spout while the shower is on). When the water is turned off, the decreased pressure lets the diverter automatically pop back up, so the next time you turn the water on you don't get an unintentional shower. The spout feels pretty substantial in your hand, and although it will waterspot, the finish wipes clean easily with a rag. Time will tell how long it will last, but the plumbers forums I checked said that the pull-down diverter spouts tend to not lime up as badly, since the water isn't normally flowing through the diverter seal while filling the tub. Even if it does scale up over time, it should be much easier to remove this spout to clean or replace it (one of our old spouts I couldn't turn off with a wrench, and instead started to twist the copper pipe, so I had to cut it off with a hacksaw). Plus, many of Delta's spouts use the same adapter, so we should have lots of options if we ever want to replace the spout with a different style. Finally, Delta does make a slip-on (solderless) adapter for use with 1/2 copper pipe. I didn't buy/try them, as I wasn't convinced that our pipes would be fully round by the time I got the old spouts and threaded nipples off. But they are available, if you have copper and don't want to learn how to solder. Like the included adapter, it gives you a good range of adjustment in terms of fitting the spout to the wall without having to have it at a very precise length.
