When I remodeled 2 of my bathrooms, I wanted to use Delta shower valves for their quality, dependability and finish. I saw what I wanted at the orange big box store, and when I opened the package, I saw it was only $160, but it felt very light. Lots of plastic, including the shower hose, which was plastic, and it coiled really weird. I went to a custom bath shop, saw the same item, but this was $380. The box weighed about twice as much. There was no plastic in the assembly, and the hose was metal. There were no kinks in the hose, and it laid against the wall smoothly. I opted for the more expensive units.
Bottom line, in my opinion, go to both the big box stores and the custom bath shops, and see for yourself.