Well, contrary to some of my own earlier postings, I have found a significant performance difference between TLA 01xx and TLA 03xx, and it comes in the form of sensitivity to FE (focusing error) for DVD-R media.
Under TLA 01xx, if the focusing error approaches 35 or so, PIFs will appear on DVD-R media which often exceed 4 for a 1ECC block. In other words, a coaster. Even if I slow the rate of burning, the PIFs are still there--and in the same quantities.
It is very reproducible, but DVD-R media is much more sensitive to it. Brand does not matter, just FE of the sample. I haven't seen this problem with any of my +R media, but it occurs on all of my -R media, when focusing errors are present.
I don't know whether TLA 02xx addresses this (I don't have access to a sample to check), but it is a definite and distinct difference between my units, and since my units are both excellent performers of their revisions, I'd have to attribute this to the TLA difference. If I had to guess, I'd think it was probably 02xx that fixed it.
By the way, CD-RW media, which uses a laser frequency similar to DVD-R, has shown problems on my TLA 01xx unit as well. I have yet to test this on the 03xx unit.
Anybody out there seeing similar results...? Please post.
 I'd like to add that I've been a huge skeptic of the TLA kerfuffle, but this one looks real to me. I'd love to see a sample (FE/TE + PIF test) from an 01xx unit on a DVD-R that contradicts this. [edit more] ...or a sample from an 03xx unit that has the same problem.