Many amps come with spring reverb, but I've never paid much attention to them. I mean I've used them in various amps I've owned, but without giving any thought to what model it is or how it was constructed. Presumably, some spring reverb units of old are better than others, so I am asking the question of spring reverb aficionados. If you could have any spring reverb installed in the amp of your choice based only on quality of reverb tone, which one would you choose? Is there any one reverb that is considered the gold standard?