Linear Tracking Turntables - Best??

Donc55 that's why the only ones I would use are the air bearing ones. 
Atmasphere the ET2 can be set with the bearing at the level of the LP.  
The ET is also stupidly well priced for what it is.  SOTA for under 1K used.  I think it's because a lot of people are afraid of it. And no it does not require constant adjustment. Once set it stays that way. 

What Atmasphere is talking about is discussed at length on several other strings. Having the lowest possible mass really helps this phenomena. i modified my apollo arm (was originally modified by Lloyd Walker to a light weight ceramic) with a carbon fiber headshell, arm wand and using a UNIverse II which is a very light cartridge. The mass is substantially less as a result and the performance is very good. Bass response is not a problem and even with pretty violent passages, i do not have an issue with tracking. The apollo arm is a very short arm compared to many others hence the need for a vacuum to ensure record is flat against the platter. There was another turntable (i think an older vyger line) that was even a lighter set up as the cartridge was directly mounted to the air spindle with no arm to speak of. 
For a long time i did not believe the issue of mass but after watching set up on my older ariadne with the bulky set up maplenoll originally had, i saw exactly what he is discussing. I never damaged my cartridge but the movement was definately there especially on a record whose center hole is slightly off. That is when i started modifying arms to remove weight. 
That being said, i really like the airbearing arms and the magic they produce with a high mass turntable like the Maplenoll or Walker tables

Oilmanmojo  

The ET2 has adjustable effective mass as part of its design. As Analogluvr knows, experienced owners know to set it up for highest vertical inertia.
This is well documented in the Et2 manual (Page 9) and the ET2 thread.

fwiw from this thread's perspective and comments from Atmasphere.

His experiences with the ET2 are documented on AudioGon here.

https://forum.audiogon.com/discussions/are-linear-tracking-arms-better-than-pivoted-arms/post?postid...

Atmasphere
Later I had an ET but after eating a few cantilevers, I ditched it. Obviously I had the wrong cartridges in it; you could sit can watch the cantilever move back and forth as the arm tried to negotiate the LP. If you have ever seen the arm 'wobble' you know what I am talking about.

@Atmasphere

From my personal experiences, No, not wrong cartridges - just set up wrong. In this case it appears from your comments that it was 1) improper set up and 2) severely eccentric records.

Page 47 - ET2 manual.

If you like to play severely eccentric records, ones with run out greater than 1/8th of an inch, then we suggest you use a low mass pivoted arm

From a cartridge end I have gone as high as 50cms/dyne x 10-6 with no issues with proper setup on an ET2.

Air Bearing linear trackers will always have higher horizontal mass. I don't know one audiophile that plays severely eccentric records. I mean Audibly what's the use. Unless you want to carve out the hole a bit and use a center weight. That's getting pretty anal !  but maybe it's a special record. 

Happy Listening.

Donc55 that's why the only ones I would use are the air bearing ones.
Atmasphere the ET2 can be set with the bearing at the level of the LP.
The ET is also stupidly well priced for what it is.  SOTA for under 1K used.  I think it's because a lot of people are afraid of it. And no it does not require constant adjustment. Once set it stays that way.

The ET does indeed have the bearing at the right plane. The problem is the lateral tracking mass. Lightening up the arm would likely help but the real place to lighten things up is in the bearing itself. Have there been any carbon fiber air bearings? I'm not aware of one, but if such were produced, it would be a simple method of reducing this issue considerably!

The fact that additional air pressure and a larger tank makes an air bearing sound better should tell you something. The engineering principle involved here is that the cartridge has to be held in perfect locus relative to the LP surface while still being able to move freely. To that end, there can be no slop in the platter bearings and the plinth must be absolutely rigid and dead such that the base of the arm moves in the same plane as the LP surface should there be vibration. The bearings of the arm must have no slop such that the arm is rigidly coupled to its base. Any difference between the locus of the cartridge and the surface of the LP will be interpreted as a coloration.

It is that latter part where the issue lies. Because there is slop is why increasing the pressure and adding a tank improves the sound. Essentially it reduces the effect of the slop. But the slop can't be eliminated entirely else the bearing would not work. Now we are talking about microscopic tolerances, but grooves on an LP are microscopic too.  The only way around this is not not have slop which is impossible with an air-bearing arm.

Now I'm not saying an air bearing arm does not work- Bruce could not have stayed in business over 25 years if the arm didn't work! What I **am** describing though is the envelope that needs to be pushed.

Atmasphere

All ET 2.0 and 2.5's are designed to work at a certain PSI.  Bruce tailored them to customer specs and he also offered lower and higher pressure models. They need to be run at the PSI as designed.
Now The problem. 

Many owners especially those in high humidity areas not using a water trap, have let moisture carrying minerals and other crap into the manifold allowing the capillaries to get partially clogged. This is when higher psi does indeed help a bit forcing more air through the manifold and the capillaries/partially clogged. Owners wrongly assume it sounds better because of higher PSI.   But its a band aid.  The fix - clean out the holes! .....and use at the designed PSI.

Many buy used ET2's and have never cleaned out the capillaries as shown in the manual.  They have never ever  taken them apart; and they have no idea what PSI they were designed for - like an ebay sale. We have discussed the procedure for how to determine the PSI that Bruce designed them for on the ET2 thread.

So one needs to filter out (pun not intended) and qualify what you read on the internet. The design also has a 19 psi limit -  if set up this way by Bruce in the first place. Like my 2.5. So if you read about someone using i.e  28 psi .......:^)   be leery.

Air Quality vs Air Volume Higher PSI. 
Don't confuse higher psi volume of air over the quality of the air delivery that is being delivered. If the ET 2.0  2.5 is operating properly it is the quality of air delivery from a better pump - not the higher psi that improves its sonics. This is proven by using two pumps, same psi differing in air flow quality only.

The ET2 tonearm more than any that I have owned or am aware of allows, invites mods.The envelope can be pushed as far as you want to go. But, first, you need to figure out how it works.  This takes time and patience and out of the box thinking since it is unique.