I’ve been listening to the LS3/5a speakers for around 30 yrs.
I beat that - bought my first pair in either 1987 or 1988 with my BBC staff discount, as my first job was at BBC Research Department and they were all over the place.
I differ somewhat from many users as I've never particularly liked the 15ohm version and prefer the 11ohm. There is a smidgeon less (false) bass but they are a lot easier to integrate with subwoofers, and I used to use old M&K mx70b subs to good effect.
The 15ohm versions always sound a bit compressed to me, and often with too much midrange, which can be a lot worse in 2nd hand examples as the driver develop a fault in the glue holding the dustcaps on (the white-belly disease) and it results in a peaked response at 1Khz. See https://ls35a.org/white-belly-disease/
Falcon Acoustics do a Q7 speaker which is basically their 'gold badge' LS3/5a but in a cabinet that is slightly deeper and matches the B110 bass driver better, and from comments I've seen comparing the Q7s to an LS3/5a version I know well, which is normally preferred by a good margin over their gold badge LS3/5a, it looks like the bigger box gives better results. Falcon Acoustics have the original Kef designer so know what they are doing and are probably the closest current version to the original 15ohm versions, the others on the market are either implementations using modern drivers (designed by probably the best BBC style designer currently working - Derek Hughes of Spendor fame), or use cloned drivers that look like the originals but may or may not perform like the originals - and that included Rogers although they have Andy Whittle to make sure they sound right, and he ran Rogers for years.
The original LS3/5as were designed an built at BBC Research Department and were renowned for their sound quality. I've not heard any but I have heard the pair labelled 001/002 that belong to Paul Whatton and, given the right music that isn't too complicated, they present an incredible soundstage/image. They sound old though with anything complicated.
One reason for their good sound is that they, and the Kingswood Warran prototypes, were housed in cabinets with 9mm thick ply walls instead of 12mm. They also had screw-on back panels, although I am not sure that is really significant in a cabinet of that size with only small distances between the screw holes.
I switched my original 11ohm LS3/5as into such cabinets around 1999 when Stirling Broadcast were lent the 001/002 pair to measure and started replicating the cabinet.
I also switched them over to use the external Cicable crossovers, which were also designed by Derek Hughes, so I never really isolated whether the cabinets or the crossovers had the most effect, but the difference from the standard LS3/5as was huge - much more detailed and transparent, super smooth, etc. No doubt some came from the huge (40%) reduction in THD at some frequencies.
However I have just sold some 9mm cabinets to someone who has been building and tweaking his own LS3/5as for years and he was pretty gobsmacked at the difference the new cabinets made compared to the 12mm, to the point of not understanding why more manufacturers aren't using them. Falcon did actually do a couple of very expensive versons with the thinner cabinets.
One reason the 15ohm versions might sound better than the 11ohm, part from the compression I seem to hear, is that the manufacturers all produced/sourced their crossovers from different places, whereas the 11ohm crossover was simpler and all supplied by Kef, along with matched drivers. That gives more scope for their being variance between different 15ohm versions.
Later I got some Stirling Broadcast V2s and then V3s - the V3s were very good and it seems from users comments that they were vying with the Falcon gold badges for user preferences. There's nearly always a preference for the midrange performance of anything that Derek Hughes designs, so this is where preferences for the V3s generally lay.
Then I happened to visit Doug Stirling a couple of years ago as I had blown a T27 and was looking for some help with the repair, and found that he was becoming ill with Alzheimers. He had built up a big stock of loudspeakers but hadn't been selling any, probably because of his Alzheimers and lack of interaction with his dealers.
As I live relatively close (60miles) I took on the challange of checking his stock and selling it to raise money for care.
After we sold all the V3 LS3/5as we asked Derek to provide more V3 grade crossovers so I could convert the V2s to V3s as they would sell easier - as I was doing this for free and mainly because I am an LS3/5a enthusiast (also owned ls35a.com for years, although I point it at Paul Whattons site) I wanted to be selling the best version rather than just a competant version.
The new v3.2 crossovers are basically the same circuit as the V3s, but because they use more 'boutique' components from Jantzen they seem to have upped the sound quallity quite a bit. Customer feedback has been uniformly excellent, notably with comparisons against that Falcon Q7 I mentioned being a bit less conclusive.
It's been a long slog (I've started so I'll finish...) but I am approaching the end with about 43 more LS3/5a pairs to sell.
The Stirlings have the advantage of the thinner 9mm cabinets and also drive units that can handle more power than the originals.
The v3.2s sound excellent, but interestingly my original 11ohm LS3/5as in their thin cabinets and with the Cicable external crossovers might actually sound better, apart from the bass being better with the more modern drivers. I also have some similar Xtracable external crossovers on my V2s and they also sound excellent, but the Cicabled 11ohms still hold their own in some areas, I think the T27 tweeter might still have the edge over some of the modern ones.
So if I was after an original style LS3/5a I would be looking at the Falcon Q7 as, because they sell direct, they are excellent value. Put a felt square around the tweeter and add tygan grills and they are an LS3/5a in a deeper cabinet, and if you really wanted that compressed, bloated and slow bass of the original then you could source some original cabinets. BK Elec often sell actual new Rogers cabinets on ebay.co.uk for arond £240.