The specs for popular self-adhered air barrier products are all over the map for air leakage.  From .04 cfm/sf to .00004 cfm/sf.  Does it make any difference at those numbers?  Or are they all airtight enough and it’s just marketing?  I suspect workmanship and detailing are way more critical than which barrier gets used? Also, is it necessary to tape plywood seams prior to adhering the membrane to get PH level ACH50’s? Thanks