Welcome to our forum.
...I hope you find a tub that is right for you. Relax a bit on all the technical stuff. The brands you are looking at are all top notch and you are going to be getting great quality all around. with the brands you are looking at, I think you should really be asking yourself, how much and what fits the best. I don't care what anyone says, when you are comparing all these brands, quality is a given on all.Good luck on your search.