I used one of these along with a Warchal Timbre set on my student violin, and indeed; absolutely no whistling tendencies on the E string! Very easy to play. It also eliminated the harsh, metallic sound I got with standard E strings on this violin. (The Warchal helix E strings have a similar effect, but I couldn't use that with the integrated finetuners on the ConCarbo tailpiece, which is why I used the KS311W instead.)
Some dislike the sound of the KS311W, and after upgrading to a much better violin, I have a theory about why that is. My new violin (professional level) sounds absolutely amazing with a plain steel E string! (Does have a slight whistling tendency, but not problematic at all, unlike my old violin, which was hopeless with that.) I think my old violin just wasn't resonant enough to produce a good tone with a standard steel E string, so the less metallic tone of a wound string matched the other strings much better. However, I suspect my new violin might just sound dulled down with this string, as it needs that steel string brightness to add clarity to the strong body resonance.
In short; great solution for the whistling problem, and might also be an option for violins with an overly bright and metallic tone on the E string.
