Outer ring - who uses and what are your findings

@brf That’s not how SME works. SME system flattens a bolw shape warped record on either side. Surface of the platter and the bottom of the clamp are machined to a specific geometry. There’s a metal disc that is placed under the record. Once the clamp is threaded on, one can adjust the force to where the record is perfectly shaped to the platter. Insanely warped records become flat like glass on the SME. You guys really need to know what you’re talking about before posting. 

The ring system on the other hand is a cumbersome nonsense. It needs to be very heavy to work properly. You guys are not only wasting your money and time during every record change, but are also changing the properties of your platter and are possibly ruining your bearings. 

@invictus, if you are referring to the SME Type 20 collet clamp, it does not flatten poorly warped records as proven numerous times by my friend who owns a SME 20 with said clamp. BTW, bowed shaped records are merely a small sub set of warped records.

@brf There is no collet on the SME. I clearly explained how it works. As I told you in the other thread, please take the trolling elsewhere. 

Never tried an outer ring, I use a Mitchell eng record clamp which is supplied with a couple of different thickness felt washers to be used under the record. You can adjust the pressure of the clamp by how much you tighten it.
I have found it works very well for minimalist warped vinyl but if you have a really bad edge warp it does not help much.
Every time I look at cost of outer rings it puts me off...lol

I own an SME Model 10 as well as Michell Gyro SE. Michell’s clamping system works fine, but SME’s is state of the art. If a record can’t be flattened by SME, it should be tossed into the garbage and life goes on. It would have to be visibly warped and severely rippled on the edge. No one should be buying a record like that to begin with. No periphery ring will fix that. 

But regular edge warps are easily fixed by SME. As the clamp is threaded, the outer part of the record gets bowed towards and pressed against the platter.