Airflow, whistles warm up method/time and vapor production seem to be the topics we're all interested in as the EVO spreads its wings and graces more of us with its presence. That being the case, the timing for my wondering seems pretty right on.
I would love to get some experienced opinions on air flow for the newer units. Wall of text coming, please forgive me...
I was able to pick up that EB that was in the classifieds around Thanksgiving. I was lucky enough to receive the unit prior to Thanksgiving - serial number would allude to the fact that this is unit #85. I had also pre-ordered a unit in August. When I got the EB unit, I cancelled my pre-order, but I saw last week that the cancel did not go through. When I got my email that the pre-order was ready to ship, I made a quick phone call and a buddy was happy to jump on the opportunity. Excellent little wrinkle!!
The pre-order unit arrived Saturday, the serial number alludes to this being unit #447. I called said buddy and he was psyched and would be by Sunday to pick the new toy up. Since the sale would be coming through me essentially, I opted to QC his heater (I begrudgingly left his glass unmolested).
Warm up time seemed the same. I set both units to my normal start up temp of 3PM and watched. Almost to the second, the two units went green together. I then dropped to 1PM for my normally preferred setting and watched again. Again, almost down to simultaneous, they went green together.
Next I took two equally lightly loaded ELBs (same strain, same grind, both slightly >1/4 full). I went to my unit first and pulled a full, thick hit exiting with a huge cloud around the light in the room. I moved to the new unit and repeated. There was much less vapor to see in the tube, MUCH less resistance to the pull, much louder whistle at the same draw speed. BUT - the exhale was a huge, thick cloud.
So I switched back to the original, pulled that ELB three more times to some popcorn flavor and repeated the process with the new unit - but it was 5 more pulls to the popcorn flavor. Interestingly, the ABV was darker in my early unit vs what I could take the more recent pre-order unit to... I did not, however run up to the 3PM point to see if I could get that dark chocolate brown ABV in the newer unit.
Both units had great flavor. Both units affected me wonderfully.
Looking down into the depths, I am relatively certain that the bottom hole of the newer unit is slightly larger (to my eye anyway).
I had a touch of a battle internally as to which unit I should sell. I opted to keep the one I have growm fond of with the more restricted airflow - with my thinking that I would likely need to use a little more temperature to compensate for the faster airflow, and I like the reservation of the top end for when my state allows us to operate in compliance of the law and concentrates become a possibility here... I also would have felt a little guilty selling ht emore used unit at full proce because I liked the newer one better - that just feels selfish, and when there is recourse avaiable to make adjustments, that just felt to be a dick move.
So my hope is that I can better understand if the more resticted unit is more or less efficient - I am sure there are are some subjective bits in there, but I really feel like the bamboo in the newer unit is physically different. If the more open path is more desired, I can pen a ticket and ask to have my bamboo updated, I'd imagine. The restriction does have the potential to make me drool a little if I am not paying any attention at all... But I honestly had a hard time defining a preference between the two - both were amazing, just... - ...diffferent from each other, if that makes sense.
TL;DR: Which do YOU prefer? More or less restriction in the bamboo?
And as an aside - EVERY person that I have exposed to the EVO has plans to buy one or has made an order. To my mind, that is an additioanl glowing review to add to the list...
I am not really all that surprised (call me a fanboy) 
(Serial number undisclosed to protect our high level security clearance) 
