Figured Id add my two cents.... I have a 7.2 system consisting of Signatures (S8-fronts, C5-center, S6-rears, ADP3-surrounds all of which are V3s. When I first got into this hobby after I graduated college in 2007 I had garbage speakers.... which at the time I thought were awesome. So i started building my first home theater.
After 3 years I had put together a system consisting of 2 pairs of studio 100 version 2s, a studio 690 v4 and a pair of studio 60 version 2s as my surrounds. I had heard the Paradigm Sig version 1 line at my local dealer (S8s, C5 and ADP3s). I thought they sounded very nice, but not all the much better than my studio line system. Around that same time there was a gentleman locally selling an entire B&W system (which included 800Ds as his fronts). I was very impressed with the sound of the 800Ds, they did sound better than the S8 version 1s that I had recently heard at the dealer. Then a little while later I decided to start on my signature upgrading. I first purchased the C5, then a little while later I purchased a pair of S8s eventually completed the system with the S6s and ADP3s. The version 3 line sounded far better than the version 1 line my dealer had in his showroom. They sounded notably more detailed and crisp, especially at or close to reference levels. The bass response was also much better. I would definitely suggest anyone who has the means to buy the signature line over the studio line to audition both lines. The signature line is considerably more expensive, but in my opinion well worth it. I now have 2 subs, each with 2 powered 18s. I use them when I watch movies and want to shake my house with 125+ spl, but when just listening to music I don't use the subs, the speakers have more than enough bass.
I have since heard B&W 803Ds, and 801Ds at a dealer while I was on vacation. The 803Ds sounded fine, not anything that I would suggest buying over the S8s. The 801Ds were notably better however than the 803Ds. They had much better bass (deeper and more impactful) and sounded much smoother to me, but obviously they cost significantly more.
So that's my two cents. I have heard a lot of different speakers and I am very happy I decided to go with the signature line. But when you're spending a lot of money, or any money for that matter, on speakers you owe it to yourself to audition the speakers. You really cannot solely rely on what you read online, ESPECIALLY in forums. The forums are good to use as a reference to a point. But everything is extremely subjective and on the forums especially you mostly just run into brand bashing by others who are loyal to other brands, it goes both ways. Therefore the most important thing is listen to the speakers before making any decisions.