I have heard them both, and definitely prefered the Salks. Very nice speakers with a great crossover design. That have a build quality that is phenominal. Easy worth the 4K selling price that Jim charges (and a heck of a lot more). Just for disclosure, I do not own the Salks, and have no connection to the company... but I am a fan.
I really am not trying to knock the 4JRs though. They are a very good value as well, and I am a big VS fan too... The Salks just impressed me more in pretty much every area. Top-end, midrange, low bass, soundstage... etc. I would still recommend the Salks at 4K over the JRs at 2.7K. I do think you would be happy with either speaker though, so I would not worry about "missing out" if you go one way or another.
---Dave