@Labpro–– Although much of this thread is devoted to DIY methods, many of us have had the Audio Desk. I owned one before the "Pro" was introduced, and based on the recommendation of some early adopters, reduced the amount of "fluid" I put into the bath- not so much for cost-savings but to reduce the potential for fluid residue. Honestly, I could not hear artifacts from the cleaning on the original AD, at least when using just a capful, rather than a whole bottle of the fluid. (Robert Stein, the importer, may disagree, but he’s not a disagreeable person).
I have shared some records with a collector friend who has the "Pro" version, he loves it, and the records sound fine when played on my system, many states away from him. In a couple instances, I have done more intensive cleanings for him, but no rigorous comparisons of before and after. My take is that you should be satisfied with the performance of the AD, and there is some benefit to the ’no work’ approach.
There were some (ahem) issues with the early AD machines and most of us moved on. I bought the KL before AD introduced the "Pro" model, but the KL doesn’t allow for a surfactant. So, it’s trade-offs. Much of the attention on DIY is cost savings over the commercial US record cleaners, but some is getting better results than what those provide through a medical/lab grade US system, the use of surfactant, control of temp, frequency, de-gassing, filtration and other features or variables that you cannot control on the ready made for LP cleaning units.
My main issue with the AD when I owned it wasn’t the residue of the fluid, but that it didn’t do as good a job on problem records- I buy a lot of used, rare vinyl, some of it in less than pristine condition (not beat up copies, but ones that benefit from more intensive cleaning, combining manual cleaning, point nozzle vacuum and ultrasonic). Others may have a different view, but assuming you are dealing with new records or older records that were well maintained by audiophile types, you should not have any issues over cleaning quality.