Time, I own both. The SARB045 with blue dial and the SARB033 with black dial.
Like John said, both watches use the same exact 6r15B movement but the main differences are as follows:
- Absence of lume in the SARB021
- Dauphine hands used in the SARB033
- Nicer, more substantial bracelet used in the SARB021
- The SARB033 uses an oyster type bracelet, still nice, but not as substantial feeling and tolerances (gaps) are not as tight. Clasp (scissor styled machined) is same for both
- The case has more detailing finishing in the SARB021. The sides are brushed and there are more complicated mill work that is evident when seeing the watch up close
- The case in the SARB033 has less detailing, sides are polished and has a strong resemblance to a Grand Seiko
- The SARB021 has crown guards whereas the 33 has none
- The minute chapter tick marks are part of the dial in the 21 whereas in the 33 they have their own chapter ring.
- The markers in the SARB021 are finely polished and hand applied. Since there is no lume in the dial, they are made to catch any little bit of light at any angle
- The markers in the 33 are not as detailed and are lumed. The lume is deficient, imho, in the 33
- Both have hand applied enamel dial color. The 33 looks metallic brown when the sunlight hits it directly and has a shimmering effect
That is, pretty much in essence, the differences between the 2. Both are simply different flavors of awesome :-*
You would have to handle both in your hands to appreciate the differences that make up the higher premium in the 21 vs the 33.
I'll post some close up pics later. I would say, the added premium of the 21, 23, 25, 45, 46 are well worth it over the 33 and 35.
Read this article here from Yeoman's blog:
http://yeomanseiko.wordpress.com/2010/04/18/6r15-mechanical-sarb045/