Are linear tracking arms better than pivoted arms?

Well, ET-2 arms are fairly cheap when they come up for sale. So, for around $500-$700 you can try one out. Make sure you use a surge tank with it and an air filter on the output of the tank that feeds the arm tube. You can build your own surge tank for dirt cheap by going to home depot or Lowes and buying a chunk of PVC pipe and two end caps and two air fittings. If you decide it's not for you, you can always put it back for sale on Audiogon and get your money back. The manual is available for down load on ET's website and Bruce Thigpen will answer all phone calls and help out with any set-up problems. You can't ask for better service than that.

Phil,I would love to hear about Julius Futterman. At one point I had the Harvard Electronics h3a. BOb

Atmasphere wrote a very good - and true - comment. That's the way it is.
When you compare those Arms on a table which can hold several Arms and you use a demanding music with a lot of dynamic swings - like the old Deccas, no reissues - you will discover very fast what linear tracking Arms CAN'T do, they are not able to reproduce a Physical Force which is in the recording (has nothing to do with volume).
The silence in the grooves based on that kind of tracking is true, but this is only 1 parameter.
Anyway, it is not necessary to split hairs, today we have pivot Designs which are not outstanding and a linear tracker beat them. The difference is pretty simple, you design a working pivot, the Designer has to think and has to solve some problems, otherwise it won't work properly.
Regular Arms can be hyped much easier, they can be made chap and can be fitted with a generous mark up.
But back to the question:

Are linear tracking arms better than pivoted arms

the answer is: No

i own both types, the Rockport Sirius III linear tracking arm, a pivoted Triplaner, and a pivoted Reed.

my experience is that optimizing a well designed linear tracker can get world class bass performance.....even compared to top level pivoted arms. the character of the bass might be different on a linear tracker than a pivoted arm. subjectively one might prefer one over another.

in my particular case i did think my pivoted arms had more bass slam than my Rockport linear tracker. then i removed the silicone dampening fluid from the Rockport arm, at which point the bass performance really came alive. the dampening fluid had been slowing down the arm, both in the vertical plane but especially in the lateral plane. without the fluid to 'push against' as it tracked sideways down the air shaft the energy level increased by a large degree.

i have 2 Ortofon A90's, one on my Garrard/Triplaner and one on my Rockport. the bass is rounder on the Triplaner, but it does not have more slam than on the Rockport. the Rockport has more articulation and tonality in the bass, the slam and decay are of different character.....more life like. i've had the A90 on the Technics/Reed. there it has more slam than the Garrard/Triplaner, maybe a touch more than the Rockport, but not alot more.

if i were to draw my conclusions from my experience with the Rockport arm with the dampening fluid then i'd likely agree about the differences mentioned above on the difference in bass performance......but not now. and......in all other matters of performance the Rockport arm 'laps the field' over the pivoted arms......but of course, it's not possible to isolate what it does from the tt it resides on.

all air bearing linear tracking arms are not the same; and unless one spends considerable time with any particular arm you cannot assume things.

"Make sure you use a surge tank with it and an air filter on the output of the tank that feeds the arm tube. You can build your own surge tank for dirt cheap by going to home depot or Lowes and buying a chunk of PVC pipe and two end caps and two air fittings."

This in a nutshell is why I have never owned an airbearing linear tracking tonearm. I just don't want to be bothered with tubing, tanks, gauges, and pumps, not to mention the noise from said pump. But if I did seek out one, it would not be the ET2. Since I don't have the scratch for a Rockport Sirius or Walker, I would go for the Trans-fi. But in the end I agree with Mike. The whole argument is specious, because "it depends". Or as Syntax said in simplest response to the OP, "no".

Ralph, servo arms have inherent problems too. The Rabco depended upon the arm swinging in a "micro"-arc so as to activate a relay that then switched in a tiny motor that drove the pivot along a rail. Thus in fact the Rabco (and the copycat Goldmund T3) transcribed a series of tiny arcs across the surface of the LP, which may place even more stress on the cantilever than does a well designed air bearing tonearm.