I've used it for years with only a one issue. There will be some that will tell you this stuff is next to snorting straight cancer up your nose but I've never experienced any side effects. Do - wash with soap and rinse the wheel BEFORE using it and NEVER let it dry, even with WB, you're going to have tro use a brush on those nasty baked on Mercedes / BMW wheels, rinse, and I use an alkalin APC to neutralize the effects and then wash with soap again - rinse. Maybe overkill but it works for me. Why use it? It works plain and simple and unless you enjoy spending a LOT of time on wheels, then it's a product you should have. I want to stress, dilute it 4:1, and only use it when it's needed, after you get your wheels clean, soap/water should maintain them or APC if you have that greasy tire dressing sling thing going on.
Issues - just 1, I (my fault) let it dry on a Chevy truck wheel and it made it very dull, I had to break out the PC, orange LC pad and a little M105 to polish it out. Then that wheel looked SO good I had to polish the rest of them so they would all match. The owner was really blown away and was happy happy happy as Phil would say.