1Z Perls is my favorite; after washing with Perls my car looks like it was just detailed. When I use a carnauba LSP I like P21S &
Pinnacle. QEW is great when I'm in a hurry or the water is turned off in the car wash in my complex.
Most of the carwashes I have used have been good even if not great. I have found that most of the time when people are unhappy with a car wash they are not mixing it correctly - by this I mean they either make it too strong & remove some LSP or they make it too weak and it doesn't have sufficient lubrication.
The method that works best for me with most washes is to fill the bucket half way, add 1-2 ounces of wash depending on the product, and to fill the rest of the bucket...the pressure from the sprayer creates good suds, although with some washes like Perls they don't really last. Some washes work better when you add them at the beginning.
It also seems like many of us who have gotten past the suds issue love Perls; if you need suds then Perls probably isn't the best wash for you...NXT wash may be a good replacement that is locally available.