I'd happily give up 9 cfm for another 30 mph. I have to wonder as well what was changed? When it comes to moving debris, cfm is the most important thing, but losing only 9 for that big a gain in air speed seems like a no brainer to me.
I'm not knocking your choice here, just curious why you chose the Echo over the Stihl? Both are great machines. Is it because of the slightly higher cfm from the Echo, or was it because of the valves in the Stihl? I have heard several guys now say that they can't detect any real difference between the two when in actual use performancewise.
I like the Stihl because it is quieter, lighter by 2 1/4 lbs (which adds up over several hours of continuous use), and because it felt more comfortable when trying them both on side by side.
What tipped the scale for you?