Calling all Vandersteen Fans

A little over a year ago I owned he 1Cis for a short time. While I enjoyed many aspects of the speaker, I found their top-end was a bit ripe and sibilant, with multiple amps. I ended up having to attenuate the treble by 1.5db in order to enjoy them at all.

Lately I've been thinking about how well those speakers produced a realistic decay of instruments, the likes of which I haven't encountered in any other speakers. I'm wanting to give Vandersteens another chance and am considering the 2CE SigIIs, however, it appears they and the 3As have the same tweeter as the 1Cis. That and the measurements in the Stereophile review give me pause. I suppose it could be that I didn't allow the 1Cis enough break-in, or that I was actually hearing upper midrange distortion from their 8" midbass driver

I'm soliciting input from those very familiar with the brand. Would you say the 2 Sig IIs produce a warmer balance than the 1Cis? Do they in-fact share the same exact tweeter? 

Is a 100 watt/ch amp enough to drive 2CEs to satisfying levels in a 26×15' room?