This is by far the best wheel cleaner I've ever used. I've used both Meguiar's, Mother's and Chemical Guys. They all worked decently, I tend to prefer the Meguiar's Hot Rims over the rest; however it doesn't come close to how well this works. With 4 piston brembo calipers and hawk hps pads, my Evo's brakes spew out a TON of dust onto my wheels. It's a constant battle to keep them somewhat clean. If I let it sit on there too long and gather more road gunk, it was impossible to get off with Meguiar's (or anything else) alone, and would require scrubbing (sometimes with a harsh/dangerously hard bristled) brush. Not anymore! This cuts through caked on rims even after a couple months of horrible neglect.You might need to use two passes with it, depending how hard caked the gunk is. My advise is:-First spray the wheels with my meguiars soap and pressure wash them to get off as much as possible before applying this.-If you have a light cleaning (usually less then a couple weeks for my car), then you can get by with spraying two rims at a time. If you're going to have to scrub some of the gunked on mess it's probably best to do one rim at a time. Spray your rim(s) generously getting in your inner rim if possible, your lug nuts, etc.-The liquid will come out kind of greenish and then turn an orangish/redish as it breaks down brake dust. It has a very strong (like cat urine) odor that you just have to get used to.-Let it sit on there for a couple of minutes (usually don't want more then 5). You don't want it to dry on the rim, although having accidentally done this - it washed off no problem.-If it's a light cleaning you can probably get by with just pressure washing it clean at this point, although to make sure you get all parts of the rims I usually go over it withGriot's Garage 15704 Micro Fiber Wheel Wand, (Pack of 2). If the caked on mess requires harder scrubbing I'd recommend something like autogeek's "speed master wheel brush".This bottle usually last about 16 individual wheel cleanings. It makes it the most expensive option out there, but by far the best and safest! It is acid free and ph balanced, and is specifically designed to be safe on all rims. I use this on BBS, Enkei, and WedsSports rims that cost over 1000-1500/per, all the time. I have no worry that this can in any way danger them. A lot of other products out there can be a hit or miss, and especially if you have refinished rims it can be very risky. My BBS are refinished and so far this has not worn it off or damaged them whatsoever. If you're looking for a bit cheaper solution, there'sSonax 230500 Yellow Wheel Cleanerto use as a refill. You can also checkout autogeek, depending on their sales, coupon codes, and shipping situation - you can usually find a better deal there.