B&W 702 Signature vs The original B&W 702 S2

I'm a huge fan of B&W. I even use my 45 year old DM5's as rear speakers. There is certainly something unique about the B&W sonic signature- like a beautiful human voice emanating from them. It's subjective no matter what anyone says. But my last piece of advice is to do the upgrade if it's not too much of a financial stretch. If it claims to correct any deficiencies without adding any new ones, it's not really gambling. B&W has offered mods of products for many years and haven't triggered any class action suits that I know of. Go for it. 

Sorry, I now realize that the Signatures are the upgrades, not an option to upgrade your S2's. Oh, well. That's an expensive option in my book, but others have taken that route, I'm sure.

This is informative, but doesn't compare the two:
https://www.youtube.com/watch?v=v6-5BR9Sebk

I’ve owned many of the recent B&W speakers, including the 702S2’s.  They were very nice for the price point.  The new 702’s are darker sounding and overall not as good a value as your 702’s.  I also had the 804D2’s,  802D2’s and now the 802D3’s.  The Diamonds are special and once heard, addictive.  I would get the 804D3’s or 803D3’s....both are great but the 803D3’s are a whole other level of wow!