I replaced the cheapo shower head and hose in our trailer with an Oxygenics and an Inox stainless hose from the website that rhymes with bamazon.
The Oxygenics is decent, but I cant say I noticed a huge improvement in flow or in HW tank longevity. It would definitely never fool anyone into thinking they were in their home shower.
The Inox hose on the other hand is awesome compared to a PVC one. No longer does water run down the old, inflexible hose around the shower curtain and onto the floor. Nor does the memory in the hose keep torquing the shower head off to the side. This will be the first upgrade I make to our new TT this spring.