I agree with gremmy and Noah (no big surprise, as my comment on the "good" convergence apparently generated this little sub-topic):
There is no such thing as "perfect," guaranteed convergence with multiple-chip devices (and even DLPs can have lens/prism issues that affect chromatic aberration), at realistic pricepoints; the engineering and QC would be astronomically expensive. The manufacturing tolerances, especially at 1920 X 1080--remember, you're talking about more than double the pixel count from 1280 X 720) are simply too tight at competitive pricepoints. No way they can afford to throw out, say, 2/3 of the optical blocks!
From what I've read about forum members' experiences, Sony now has spec'd the Ruby's permissible quality tolerances as +/- 2 pixels (although I think they started out at +/- 1 at their repair facility, when the Ruby first came out...+/- 2 seems a little high). Surely, the Pearl will be no better in terms of spec'd "within the norms" repair tolerances (although hopefully better at de facto tolerances--they should be tightening their processes continuously...CPI and TQM and all that).
To have only one color one pixel off in only one dimension (especially blue), I find quite acceptible. (And, we don't know whether the convergence WAS perfect, elsewhere on the screen...perhaps they were concentrating on worst-case!)
Lastly, notice I originally said "good" convergence, not perfect...
My 4 cents...