Can you try out a Wilier Cento SR before you buy? I owned an Cento 1 and loved the quality of the "magic carpet ride" so much, I upgraded (or maybe downgraded) to the Cento 1 SL. Although the SL is lighter, I was surprised to find that its ride quality delivered significantly more road feedback in a harsher way. From what I've read, the SR is going to be even stiffer than the SL, and was not designed as a comfort bike but more as Wilier's entry into the aero frame market.
I think you've got confused somewhere. The Imperiale is Wilier's 'Aero' (ish) bike, the Cento SR is built to do all the same things as the previous Cento1s, just that bit better.
A colleague has had his SR for about a month now and says it is an extremely comfortable but responsive ride (though that is compared to an Addict). If it's anything like my Zero.7 to ride (which I hugely prefer to the C59 I tried) it'll be a lovely place to spend 100+ miles.