The airflow figure means nothing whatsoever as it isn't blowing air unobstructed
For consumer/end user none of the advertised figures means anything except RPM and fan size which give somekind hint about airflow performance compared to other
similar design fans.
Can you find any correlation between actual measured and advertised airflow?
http://www.silentpcreview.com/article695-page1.html
http://www.silentpcreview.com/article720-page1.html
http://www.silentpcreview.com/article739-page1.html
Also if you ever see specs of fan "family" claiming that say, 50% higher speed version has 100% higher airflow you know they're lying. Without back pressure airflow changes quite precisely in direct relation to fan speed.
http://www.madshrimps.be/?action=getarticle&number=4&artpage=4130&articID=936
Max cfm through a radiator is 35cfm @ 62dba and as you can see that the Typhoon comes out tops for performance vs noise through restricted coolers.
Noise measurements definitely aren't very accurate for real use because of distance and graphs telling nothing about annoying noise details...
Airflow again can't be translated into case fan/low impedance heatsink use because of high impedance radiator and measuring method probably isn't very accurate considering problems into which SPCR run with impeller anemometer...
http://www.silentpcreview.com/article734-page1.html
looking at the gentle typhoon blades their increased 'reach' as it were does seem like it would maintain static pressure better than traditional blade design.
That forward swept blade at least resists tendency of air to try to move centrifugally/radially instead of axially and lack of wide gap before next blade again limits airflows ability to try to slip backwards if there's major back pressure.
And again by looking size of big motor hub/small airflow cross section area you can deduce that in free air/low impedance it can't have high airflow/RPM ratio.
(noise again depends also from bearing and actual airflow so that goes differently)
Xigmatek XLF-F1253 fans fitted to my rad, and they are really good, even spinning at full speed they are fairly quiet.
Which really tells only that you either live in noisy environment or your hearing is on its way to retirement:
For normal design fan 1500rpm is always noisy already because of airflow/turbulence noise.
Then materials give high probability for resonances, and
blade trailing edge/motor strut design isn't optimal.