Spring water is not ideal for brewing anything other than stouts, because it is usually very high in CaCO3 from the limestone - you do get pH problems with it.
For the most part, just using RO water with enough flavor ions (Gypsum, CaCl) added to get to somewhere between 50 and 100 ppm of Ca will almost always produce the proper pH without further adjustment, unless you use lots of roasted barley or acidulated malt.
I believe 5.2 adds a bunch of Sodium to the beer, which is not ideal. When I use it, I use it in the sparge water to prevent tannin extraction, and use other salts for mash pH adjustments where necessary.