Micro SX-8000 II or SZ-1

No matter if you use the RX-5000 or SX-8000 II- the advantage of a proper aligned flywheel in opposite position to the motor drive is in the fact that the bearing will be free of horizontal force.
This will minimize bearing noise to the lowest possible - in any bearing.
The result in sonic terms will be increase low level detail, ambience and dynamic transient resolution.
Important factor is, to bring the string/belt tension to equal level (as close as possible) on both - flywheel and motor.
So - the advantage has nothing to do with bearing type - its a simple force vector model of two forces eliminating each other.

Fm_login, sorry, but I am way past that period in my life when I was young and angry enough to react to a comment as sophisticated and throughout displaying deep audiophile and mechanic insight as yours.
Sorry that basic vector geometry is BS to you.
But that is certainly not mine nor Micro Seiki's problem.

What is here disputed about the Micro Seiki skeleton TT's was already done so widely and brought to conclusion by the later 1980ies.
Micro Seiki introduced the Hs-20 and HS-80 to further improve the performance of the RX-1500, RX-3000, RX-5000 and SX-8000.
This enhancement in performance was founded on increased inertia and decreased noise and wear in the lateral bearing because - proper applied and aligned (no problem at all - belt or string, you just need balanced distance, equal length or a decent spring-tension-gauge) - the lateral bearing is force free.
This - BTW - works on most if not all (direct TT's are an obvious exclusion and Idler-wheel-drive needs some different treatment) TT's, as it is a simple mechanic principle of force vectors eliminating each other.
Each and every bearing with a shaft - i.e. with a lateral bearing - being addressed by a string pulling towards the motor in order to apply any tension on the medium (string, belt, tape) spinning the platter will benefit from the elimination of that one-side force.
Lesser noise - lesser friction - lesser wear.
Its obvious - a simple sketch on a sheet of paper does illustrate the point and principle very nicely.
The dampening of the "bell-platter" of the big Micro Seki's was addressed by Micro Seiki's copper-mat and in the early 1980ies by several soft and hard platter mats introduced by japanese manufacturers to better or lesser results.
I have too seen Micro platters damped inside (not easy done with good mechanical results, as the coating has to be done very precisely and homogenous so to not ruining the inertia force of the platter) with very good results, but these were all further damped with acrylic-mats (glued to the platter...) on top of the platter.
The improvements with inertia units by Micro Seiki or custom made devices are sonically apparent to all audiophiles who care, whose set-up is capable to show it and whose hearing isn't deafened by dogmatic prejudice.
This - for once in our audiophile world of often nebulous results and experiences - is fully backed up by applied science and simple mechanical laws found in every middle high-school physics book.

And yes, - I have used the RX-5000 too and am currently using a highly modified RX-Micro Seiki ( 4 inch double platter with isolated spindle (no contact to bearing) and 38 lbs highly dampened platter - gun-metal and PVC) and will soon incorporate an inertia unit similar to the HS-80.

Its not about using a belt at all.
I would never use a belt - not on a Micro Seiki nor on any other "belt drive" TT.
A belt is always a source of instability and in worst case much more than a filter.
The RX-5000 and SX-8000 were designed by Micro Seiki to be used with string for best results.
With a string, fairly low tension and symmetrical positioned inertia unit we are looking at a kind of slip regulated drive.
In other words - the inertia providing the speed stability and the low tension string applied without horizontal force is just preventing the platter to get slower.
Its a tricky idea and it only works with fairly heavy platter (= high inertia) and force free low tension string drive.
No belt - no tape - no high tension and no horizontal force vector.
There were papers in japanese magazines floating around by Micro Seiki engineers in the early 1980ies addressing this principle.
And yes, - there were top-class set-ups with SX-8000 and RX-5000 w/inertia units and mats dead quite already in the early 1980ies - this is nothing the US-audiophiles discovered.
Some of the japanese audiophiles were already enjoying this when the majority in the western hemisphere still thought a scottish TT would be the very pinnacle of analog set-up.
Setting up precisely a RX-3000, 5000 or SX-8000 that way will provide you with the utmost speed stability and an extremely low noise floor and outstanding low level dynamics.
I know it - I've done it a few times.
Despite what some people may say otherwise, anyone in the position to try should do so and find out for himself.
I know that some here have already done so and know that there is much truth in what I've said.

Well, - on the other hand (chinese doesn't have that much in common with japanese as it might seem from the western point of view....) there was true audiophile high-end in Nippon VERY different from what we think/thought by looking and listening to Technics and Sansui low-fi ss amplifiers in the late 1970ies.
And western Jazz and romantic european symphonic Classical music was - and is - big in Japan.

There were sophisticated SET-amplifiers, complex super high efficiency horn loudspeakers and big analog turntables widely common in Japan by the late 1970ies.
But - I admit - not in late maoistic China.......

We just didn't noticed back then.
We thought the low-fi components they exported and sold to us were all they knew and could do.
Big mistake.
Most - if not all - what we "discovered" in the 1990ies was imported via France from Japan with a solid 20 year delay.

Thuchan, I could not agree more...
Preconceptions and "experiences" long gone and the result of different conditions no longer apparent, do sometimes cloud the sight and most often do serious block new paths which could lead to much better results.

SET amplifiers, LCR RIAA triode SRPP-preamplifiers, big string driven TTs, complex super sophisticated horn speaker systems were all there in Nippon as far back as the early 1970ies.

The low-fi amplifiers exported and sold to the western hemisphere were not the best they had to offer.
We just thought it was.
In fact the japanese high-end audio scene were 20 years "ahead" of us back then.
All what was "discovered" in the early 1990ies was in fact imported from Japan via France.

******On the more serious side, I got some other then comic relieve hearing about the function and performance of tt's: >> “best quality PERFORMANCE” has absolutely nothing to do with a topology of quality of your or my turntable. << ****

Well - having learned this now, we can rest indeed in peace and concentrate on cartridges and tonearms....
Or maybe "best quality performance has absolutely nothing to do with" these parts of the front-end either...?