JSF35X: (How did you come up with that log-in ID??!!)
You are correct: there are a lot of request for and questions about the "Holy Grail" for a car wash soap.
I myself use
Meg`s Detailer Line D110 Hyper Wash after seeing it being used by Autopian All-Star Rasky1 in many of his details. This car wash soap offers long-lasting foam/suds, great lubricity, good cleaning, and rinses clean with my semi-hard Lake Michigan-sourced municipal water supply.
I have tried your fore-mentioned
Optimum Car Wash Soap, but it did not rinse clean with the semi-hard water for me, so I looked for something else.
Prior to that
Meg`s Mirror Glaze M62 Shampoo & Conditioner Car Wash was the "Holy Grail" and my go-to car wash for my two-bucket method.
If you are forced to wash in the sun, then
McKee`s 37 SiO2 soap is the ONLY soap I know of from experiences and reviews in forum that works in that situation. See this thread by now-deceased highly-respected Ronkh:
https://www.autopia.org/forums/deta...294-ultimate-torture-test.html?highlight=wash
This soap is suppose to work well in hard-water also. See post #9 in above llinked thread
When talking about car wash soaps, there are so many types and car wash methods to consider:
1) Traditional two-bucket wash
2) Foaming lance with power washer or home water source (garden hose)
3) Rinse-less wash
4) Coating maintenance wash
5) Pre-coating or any last-step product (LSP) prep wash
Each one has its own wash soap and which ever category or method you use will depend on which wash soap you find works best for that type.
No, it is not an easy answer and I do not believe that there is "one-soap-fits-all" for vehicle washes.
Even as a hobbyist, I have:
Megs D110 Hyper Wash for my 2BW
Rain Dance Heavy Duty Truck Wash for really dirty 2BW
Turtle Wax Max-Wash for added cleaning power in some 2BW
Megs M62 Shampoo and Conditioner left over from previous 2BW
Optimum No-Rinse for no-rinse washes or spot cleaning (bird-bombs)
Value Gard Decon System samples that I have never used (sent to me as a "Thank You" from Valu-Gard for pointing out a BIG website pricing error)
Turtle Wax Hybrid Solutions Ceramic Wash for use with their one-step Ceramic Polish &-Wax and Ceramic Spray Coating because it is a "poor man`s" over-the-counter ceramic coating system (I used it Sunday, 19 October, in REALLY cold weather for the first time on wife`s Ruby Red Metallic 2015 Ford Taurus; meh!)
Chances are most serious detailers, both hobbyists and professionals, have multiple car wash soaps in their detailing arsenal for a specific wash tasks mentioned above
I am somewhat interested in
3D`s Nano-Pail Super Pre-Soak and Nano-Pail Super Soap for prep wash and regular wash, if any Autopians have tried these car wash soaps. If there Pink soap is popular and good, I thought these might be a step-up from that.