Through Phil over the last several orders, I have bought and tried out four wheel cleaners. I though the following would help anyone make a decision. I plan to post picture comparisons the next time I do a full wash. For the record, I wash my car in some fashion about every 5 days. I pull my wheels every other month and get both inside and out. I put about 300 miles a week on my car, a lot of stop and go traffic. It's a Porsche and generates a lot of brake dust. Sonax Full Effect Sprayer - Weak. I don't know what it is, but the sprayer doesn't "spray" the product on. Some bottles spray a more direct stream than others. Scent - Strong but doesn't remain with the car. Effectiveness - On a scale of 1..10, I give this an 7. I say this because with the weak sprayer, you have to use quite a bit to disperse evenly, then some agitation is required. Sonax Wheel Cleaner Plus Sprayer - Excellent, will produce a spray mist! I will say this is a welcome improvement! Scent - Medium, not as strong as Sonax FE. Effectiveness - On a scale of 1..10, I give this a solid 10. This is the benchmark now. It is the first time I sprayed on, then rinsed a wheel clean with a regular garden hose. With each of the other products, some agitation is always required. Tonight, I sprayed all four wheels and rinsed. Totally clean - rotors and calipers too. Adams Deep Wheel Cleaner Sprayer - Excellent. Can use spray or stream. Scent - Strong but not unpleasant. A little perfume'y. One note, this scent seems to remain for some time. I can smell it in the garage the next day as I keep my car garaged. Effectiveness - On a scale of 1..10, I give this a 6. As long as you combine the use with agitation, it cleans well. You have to use quite a bit though and the scent just doesn't do it for me. Doesn't seem as potent if the wheels are wet. I have used two applications and still found enough "dirt" bleeding from places on the second. Einszett Colourtech Wheel Cleaner Sprayer - Excellent. Scent - Strong but not lingering. Effectiveness - On a scale of 1..10, I give this a 8. Each time I used this it was a surprise. I honestly think this cleans a little better than Sonax FE, perhaps because it is dispersed equally out of its bottle and I didn't feel like I had to use a lot. Any of the four products you can't really go wrong with as long as you incorporate brushes or woollies at the same time. It would probably come down to budget in the end. Sonax Plus is the highest price but does clean better right out of the bottle. Im thinking I wouldn't need to use a lot. The sprayer is wonderful, and the smell not as strong as Sonax FE.