I like a tight draw too. I admit the sliver is very small how I like it and it's not particularly easy to get it where I want it and a PITA considering I take the cap off every time I fill the well. But it can be done. This is another reason why I turned to the Achilles because it has a screw on cap and there is no fiddling with air re-adjustment every time it is filled.
Ditto that, on threaded rather than o-ring topcaps -- the main reason I haven't given up yet on my Magma, and probably will even go to the extreme of trying to mod it with those 12ga needles, whenever I remember to order them.
Andria