Beecharmer - BEAUTIFUL AVATAR!!!!!
I'll be going with Screened Bottom Boards this season. Bees (by the way) were flying well this morning, they went through a tremendous amount of honey the last month - SPRING is indeed a real killer, their activity level is raised and consumption seems to increase with the anticipation of replenishing food sources, which sadly don't always come in time.
As Robo has pointed out in a previous post concerning this topic many months back, a small screened hole will likely get filled over come winter - but they won't do anything with vent holes as Robo has in the photo (the one with the internal feed jar - which obviously doesn't vent in that photo) but does when using that super as a upper super filled with frames.
My point (I do get to them eventually - lol) is good venting is a superior way to twart swarming and the sooner the better. In our Chat Interview with Howland (I think you were there??) he said it isn't made for mite control, but for estimation of the degree of a mite problem. But the SBB seems to be the best way to STABLIZE the air temps in the hive WITHOUT causing a chimney effect - which could be an unwanted thing.
Example: if you have good top venting, you will also have a good flow of honey, wax and bee smell filling the air and flowing in the wind possibly attracting opossums, skunks, bears and more.
Using a screened bottom board equalizes the temps well by allowing air outside and inside even out, but doesn't have as much of a DRAFT, the air sort of dead-ends in the hive (compared to the ventbox) just a thought.