Earlier Rogers Ls35a 15ohms sonic differences Vs Later serial# Roger's 15ohms?

Few have said the earlier 15ohm Rogers Ls35a's sounded better than the later higher serial number 15 ohms versions. Is there any documented confirmed proof of this?
The only minor indication is the early serial numbers fetch more money but thats not a proper sonic indication. Could be more of a rarity value.
I do know the woofer of the later versions are a bit different because they say first versions had a flaw. 

Whats your listening experience tell you about earlier and later models?
My friend worked as a repair tech at a local hi fi store and examined the crossovers in some Rogers LS3/5A's. He noticed differences between early and later ones. Sonically I heard NO difference! 
@roberjerman good to know. Did you notice the earlier woofers were bit different around the rubber surrounds of the earlier than later serial numbered ones?
I don't remember seeing a difference in the KEF B110 woofers used in the LS3/5A's. They were supposed to be selected and matched per pair. My tech friend said that the earlier versions used an autoformer in the x-overs. As regards sonic differences years ago Hi Fi News did a comparative survey of various versions (Rogers, Chartwell, Goodmans, etc). You might want to check it out - I found it fascinating reading! BTW I own a later production pair made by Rogers.
Amazing speaker @roberjerman. Very Sweet in mids and fills a room. With vintage equipment it sounds awesome. Are yours the 16 ohm version? I heard the 11 ohm version through nad amp. They sounded terrible with that amp. The rogers 15 ohms are the best sounding. They sound amazing on vintage amps
My pair are Rogers 11ohm serial no's. 39269A and 39269B. Amps in use include: Dyna ST70, Harvard Music Futterman H3 OTL, BEL1001 and a Tim Rawson F5. Also a Quad 303 and 405. There have been many small speakers but the LS3/5A still takes first place for its ease and naturalness of sound!
@roberjerman phenomenal speaker 
Have you ever listened to a pair? They defy their size