I've gotta say it: I don't think overly mineral-rich water improves English beers or hoppy beers. Having done extensive experimentation on this, my palate prefers beers with 50-150 ppm Calcium and a balanced 50-100 ppm Chloride and 50-100 ppm Sulfate. With maltier beers, I will favor Chloride to Sulfate 2-1 and with hoppier beers, I will favor sulfate to chloride 3-2.
I have had a lot of real ale in England and I don't think they are all using highly mineral-rich water, either. When I taste a homebrewed bitter or an IPA that is too rich in sulfate, I invariably find it harsh and my sulfate-rich beers have been marked down for "harshness" and "astringency" by competition judges. I just don't think it improves things to go overboard in minerals, even if it may be more historically accurate. For my mouth, having 50 ppm calcium and good pH is what matters.