I don’t think that is a very good analogy. The FVIR stuff was forced on the manufacturers by the federal government and it has mostly been a catastrophe for them.
Bradford White has a pretty good FVIR, but there are other things about Bradford I’m not crazy about. You can’t check their anodes without wrecking them.
Rheem and Smith have engineered around their FVIR problems, although you’ll see the bad reviews of their older products for years to come, because anything that goes on the web, stays on the web.
Bocks don’t have FVIRs because all the heaters they make are more powerful than 75,000 Btu.