I don’t believe a “best” touch-less is possible because it would have already emerged.
Consider the comments, there is no consensus. There is never consensus on this subject.
The reason is people have different priorities and preferences.
For example, one operator wants affordable, fast and easy to work while another wants to clean lots of trucks in a tough environment while another wants longevity and built with the operator in mind. What operator?
For example, the primarily market for most in-bay OEM’s used to be oil companies. Now it’s c-store owners. C-store owners want a service network and longevity is less important. The reason is in-bays are only built to last between 5 and 10 years.
Moreover, if water/sewer cost increase and/or the area is subject to drought, restrictions, etc., touch-less would increase investment ownership and business operating risks.
Mitigation is reclaimed water but it’s difficult to make this work with touch-less only.