KEF XQ40 & 104/2 vs Vandersteen 3 & Mac XR1051

These 2 KEF's are available locally (a req for me) and I'm wondering, what would the XQ40 sound like compared to my V3's ?
Same deal with the 104/2 and either the V3's or the 1051's...

Would the KEF's be an upgrade to both, one, some ?

I listen to Barbra Streisand lately...just a phase I'm going thru, but can she SING :)
I don't know about the Kef's but my Vandy 3A Sigs. will never have to reproduce the sounds of BS. She's creepy...