Kohler does the job fine for resale, no need to shell out Grohe money if you’re leaving in 2 years. Had similar setup with sloped ceiling and Kohler Purist line worked nice, looks clean enough and no buyer gonna check what brand is behind the wall

Maybe check if you can find Grohe on sale though, sometimes they go 30-40% off in random websites and then it’s worth the extra

I found grohe to be reasonably priced for quality that matches and exceeds the higher end of kohler and Moen

I’ve done a few jobs where ultra stylish high end accessories were specified, and over the years, I’ve had to service those same products for seizing or finish issues. In all cases, those mfg specify using water and a soft cloth for cleaning them. No cleaners or chlorine based products allowed. Stick with popular name brands including Grohe, which I rank slightly higher than Kohler.