That test was done in 2004, there have been some changes since then. You can notice the ion reg isn't on the chart, nor are a lot of others (cp, verticla max-flo, evolve, etc etc etc etc). None of those regs were out yet except for hte old Flo.
Yes, the Ion reg is faster than the CP vert. It's been tested and proven by several completely independant pressure tests, one of which I did personally.
Consistency has a lot to do with the reg base being broken in, and other factors not even related to the regulator itself. I wouldn't suggest arbitrarilly stating one reg as more consistent than another just due to how it performed one time out on the field (or whatever the case may be). Just about anything can impact the consistency, including temperature, air fill dirt, o-ring tolerances, base seat tolerances, and just about anything else involved.
Andy "Ydna" DuBuc
As told by Stobaeus
...someone who had begun to learn geometry with Euclid, when he had learnt the first theorem, asked Euclid "What shall I get by learning these things?" Euclid called his slave and said "Give him threepence since he must make gain out of what he learns".