Outer ring - who uses and what are your findings

Uberwaltz,
I apologize , I had tried the ring a few years ago ,
Vinyl Nirvana was using them on their upgraded AR turntables ,
I looked at the web site after I posted and was surprised to see all the Thorens tables. Shortage of AR's ? 
But I suggest you keep checking the web site for a used Merrill Heirloom tables that they have once in a while .
Check out the AR & Thorens Gallery Mike Castellana's " Heirloom-ette "
or My ( Daves of Vinyl Nirvana ) Refurbished Merrill Heirloom in the AR Turntable Resources .
Contact them to see if ring clamps are still available .

See also: https://techne-audio.de/plattengewichte/plattengewicht-aussenring-turntable-outer-ring-edelstahl.htm...

at  €399.

@vair68robert. 
Thank you for the extra info
@melm 
also appreciate the site info for cheaper options
Cannot see myself changing out my Nottingham Analog table anytime soon and have not seen or heard of anybody running an outer ring on one of them but who knows?

I use a TTWeights TTMega 1.2kg ring weight in addition to a 1.4kg "Nugget" centre weight, for EVERY SINGLE record that I play. The innovative way that the TTWeights ring is centred, makes it a no-brainer to use it. The difference with mildly warped records is nothing short of miraculous, but the audible improvement with normal flat records is profound! I have several thousand vinyl records.

I cannot attest to the performance of this combination on other turntables, but it categorically improves the musical reproduction on mine from excellent to exceptional.

For the record, pun intended, my vinyl system is as follows:

• Once Analog Mk 2 belt drive turntable with fully upgraded spindle and bearing and top-of-line DC motor / electronic speed regulator
• Audio Origami PU7 tonearm
• Lyra Kleos LOMC cartridge
• JLTi-reengineered (Custom Analogue Audio) Eastern Electric MiniMax tube phono preamp with NOS Mullard 12AT7, 12AX7 and 6X4 tubes
• Interconnects and power cables by AntiCables

I did that ritual for 5 years on my Classic 3 and it became so routine I didn't really think of it as a choir after a while. However, when I changed over to the Spiral Groove SG2 with Centroid Arm I was pleasantly surprised how easy it was to flip a record over.  All kidding aside, I definitely thought on the VPI Classic 3 the peripheral weight was worth the effort. However, I am happy now I have a table that doesn't require it. I also have the option on the Spiral Groove to use a washer and dish the record to the platter. I found that most of my records don't require it. So I ditched the washer also. Put on a record, thread in the clamp and done. 
Threading the clamp with a washer is non trivial, since to do it correctly, you should spin the record to see if you have enough dish for the corners to meet the platter. Too little and they don't meet, to much and it bows away from the platter.