I have the SVS and an Anova and I use the SVS much more often. In my experience it holds to temperature better and more uniformly, the heating element spans the entire base so it's easier to cook in bulk (without worrying too much about blocking convection), I didn't have to hack a lid together, and it looks a lot better on my kitchen counter--which is important because it never leaves the counter, I use it five to six times a week.
I'll use the Anova (which I got for free, I wouldn't have bought it otherwise) if I need a very large bulk batch of something that I'm not worried about keeping at a precise temperature, but the SVS fits me a lot better otherwise.
the SVS is accurate across the horizontal plane, but not across the vertical plane. I couldn't trust a water bath without active circulation ( I use a Sainsare at home, and at work, we use PolyScience circulators)
I guess maybe it's neater and more self-contained? But the reason isn't clear to me today. They may have been reasonable alternatives to $800 Polyscience units a few years back but I don't see why the typical consumer would buy one rather than a $150-$200 immersion circulator.
