One turntable with two arms, or two turntables with one each - which would you prefer?

One turntable with one arm.

But my arm is the Simon Yorke Aeroarm that is an air-bearing parallel tracker.  Alternative moving carriages (arms) can each be ptr-set up with a cartridge and swapped out in a couple of minutes - only need to slide the carriage on the bearing rod and disconnect and reconnect air-line and signal plug.

Best of both worlds, and parallel tracking too.  State of the art for ultra low-mass MC carts up to 10g such as vdH Colibri and Ortofon A95, both 6g.

@pindac I had no problem with my VPI 19-4 for vibration relief-it has springs and rubber feet.   I almost gave back my VPI TNT VI because it's feet are next to worthless for isolation, even sitting on a heavy steel stand with 50/50 sand/shot filling.  I immediately purchased the Townshend seismic sink and placed the VPI on top of a 1.25" thick HDF board.  I used a large weight to balance the table.  It's works great for 16 years now.   If I could afford to, I would replace it with a Kronos Sparta table.   

I have looked into Kuzma Design TT's, and the discoveries made are in keeping with the Design and Materials for a Bearing Assembly of which I am an advocate.

The Kuzma selection of materials is also similar when compared to selections that other Third-Party Bearing producers are offering as an upgrade for Vintage TT's.

From my experience these types of materials when in use are able to bring a new presentation that is a noticeable improvement.

I have discussed this in previous posts and see no point to elaborate in the Subject.

From my end, if an intention is to make a change to a Set Up, with the intention to achieve an improved performance from a Vinyl Source, keeping the focus closer to home, and looking into how an interfaces can be improved, can prove to be quite valuable.

I have the pleasure of being regularly demonstrated a Standalone Pod Mounted Glanz 12 Inch arm, with a Miyajima Cart', used on a SP10R on regular occasion, it never fails to impress.

Isolation that functions as a support, has little to do with maintaining the critical geometry between Tonearm and Bearing Spindle.

I am not aware where there are claims that the Spring Suspension has the additional function of managing energies transferred through a Plinth as a result of the TT's operation. 

A Spring Support needs to be adequate as a support to ensure a Platter can maintain a Level Set Up and needs to be effective at reducing the ambient energies that are able to be transferred into the system during operation.

In general, the energies needing to be dealt with are not known, as the methods required to accurately measure the presence, is not in use with the average TT user.

The familiarization with different materials and assemblies for a Plinth Construction is the only method I have adopted and used to make my own assessment.     

Most materials chosen as a Plinth Material have poor Damping Properties and inefficient dissipation.

It is not possible to ensure an individual that if they adopted a Plinth Material that does have desirable damping properties and efficient dissipation, that they will perceive it as an improved experience. 

It is an individual's preference for a certain type of SQ that will dictate this.

I am now feeling confident that after having experienced a reasonable quantity of Plinth Construction, that the use of Densified Wood Material as a Plinth is the best method for myself.  

I have two tables, one is a SOTA Cosmos Eclipse with a SME V, so a 1 arm 1 table combo. With a suspended deck its really not possible to run two arms on it.

The second table is a Scheu Analog Das Laufwerk No2 which is an 85 pound non-suspended deck with two Dynavector DV505 arms on it. No suspension issues, so it is suitable for two arms.

The phono stage is an Esoteric E-03 that allows for two separate inputs and each side has cartridge loading options. With this arrangement I can compare two cartridges with the same arms (Dynavector) and same phono stage, along with the same drive unit (Scheu)

However my typical arrangement is using an Ortofon MC2000 on one Dynavector arm and the T2000 transformer into a Graham Slee Accession phono stage. The second arm gets a casual listening cartridge like an Ortofon MC3000 I have into one input on the Esoteric. The SOTA has a Transfiguration Audio Proteus on the SME and goes into the other input of the Esoteric.

But with little difficulty, aided by the fact that the Dynavectors have removable headshells I can set things up for cartridge comparisons on an even playing field with little difficulty.

But I did toy with the possibility of one good table. Locally there is a Walker Proscenium available. If I sold most of my analog stuff off I could afford it. But I am not sure where I would put the air pump, and now that Lloyd is passed not sure how to get it serviced if need be, and I think the gold trim on the arm is ugly. Besides I have my doubts how much better it can be versus my SOTA. I am not willing to risk everything to find out the answer to that question.

I wouldn’t go near the delicate TT101 (I chose the TT81), however, Halcro, member here did, went thru all to achieve perfection, then proved that the DD motor was able to maintain perfect speed when 1/2/3 arms were simultaneously playing.

I went with the conventional vintage JVC Victor Plinth, he made custom and separate pods for his 3 arms. And, dust cover??? one of the reasons I stayed with the JVC design.