Even if we did like Masters ethics and products, you should still look at other brands and compare tubs and dealers. This is big money. You should get the best quality available to you. Maybe that's Master but if you haven't looked elsewhere how will you know?
Don't get one because the brand is endorsed by a swimmer getting paid to endorse a product. That's probably the worst advice you will get when you think about it.
Master doesn't make a bad product. But IMO there are manufacturers with better reputations.