Philosophy: Bearing vs. Unipivot

Dougdeacon has articulated a far better answer than I could, and I very much concur with his final phrase about the devil being in the detail. I think that arms such as the two Caliburn ones (Cobra and Copperhead) are both 9 inch uni-pivots which illustrate that execution is the most important thing. I personally was a bit ham-fisted when I first ever used a unipivot moerch and was put off as a result. Some say gimballs are more evenhanded overall, it may be due to not being able to pivot in the azimuth.

In response to Ivor, Naim made the ARO. One of the simplest forms of Unipivots. The ARO till date fascinates more Linn-ies than all the Linn tonearms put together :-).

Ockham's razor is just as sharp as ever.

?? I'd be interesting in seeing how that applies here.

I don't like unipivots because the bearing is so easy to damage. I've never seen an older one come through the shop that did not have a damaged bearing. It is the Achilles heel of unipivots.

Its not like gimballed arms are perfect. Damage to their bearings is a problem too. Some manufacturers solve it by leaving some slop in the bearings, which can cause coloration. Others like SME, use larger bearings that are harder to damage (and have more sticktion). Triplanar uses a small bearing that is ultra-hard, in fact the hardest made, which is why they have consistent performance year in and year out.

I also prefer gimballed arms because they hold the cartridge in better locus with respect to the groove itself.

I want to thank you all, and to Doug have just a couple of comments for clarification. I understand that one part moving on the point of another constitutes a bearing. Perhaps I should have specifically named ball bearings, but then folks may have thought that I didn't know that knife edges were also bearings. Having a stylus captured between both vertical and horizontal ball bearings means to me that, apart from micro movement from bearing slop, the stylus will maintain azimuth, and will not tip to the right or left in the groove. That right or left tip is what I meant by relative movement. The same thing can be said for the old Rabco servo driven arm; it was always in front or behind the angle the groove was cut at. With this relative motion is a loss of information from the groove.
I know that there are many unipivot tonearms that are astonishing, so obviously these problems have been scotched, if not killed. Like you, and architect Mies said, God is in the details.