Sorry that I can't answer many of your Qs, but ultimatelly, try to listen to all ofthem, then pick what you like most.
I only heard the current Monitor and Studio lines.
I only heard the v1 version of Sigs.
Went with the Sigs....because of sound quality and the deal I mad eon them (I think).
Perhaps v2 will be better, in one way or another - I don't know.
For my budget, i tried to find the best sounding (to me) speakers.
As everyone here will repeat this: buy what you like and/or can afford.
My S4s have very details highs, and great mids.
Don't pay att. to them with respect to bass, as the SVS subs take over in that dept.
I try to enjoy the music, and not bother myself with every single aspect of sound; I guess I'm not as much of a purist/audiophile as some other people are.
...I don't need to be.
Just for comparison, everyone thought the wife and I were crazy when, time after time, we kep saying that Deftecs (no matter which) we auditionned sounded "bleh..."
We fell in love with Paras - but everyone is different.
Listen to yourself, not the dealer. If you make a wrong decision at least you'll have no one else to blame.