B&W Nautilus 802 vs. ProAc Responce 2.5

To Tweed; what kind of ProAc do you have? I have ProAc Studio 250 but planning to upgrade to Responce 2.5 or B&W N802!
The 802 cost a lot more than the 2.5
Do anybody know if it is worth the ekstra money from ProAc Studio 250 to Responce 2.5???
I Can't compare, they are to far away (used speakers).
Thanks
Yanomami

Thanks for your advice, it is great to hear your highly professionals advice. I think I will try to upgrade to Responce 2.5 so, but how would they sound with ML?
My problems could be, that my Cary's are only 40 watts and now I have some problems with driving the Studio 250 is the 2.5 easier to drive?
I have heard some SS amps and I like this fast acurate sound, which are the reason I plan to change!!!
Yanomami

I forgot to say, that my listening room are 4,5 * 4 meters and my equipment are all highend tubes pre/amps with the highest levels of cables from Vantage (the best in my opinion). My cd player are ML 36s/37.
Yanomami