i had the adjustable one, and adjustred it without it attached. didnt notice any difference at all. i didnt however, have a madvapes one. the one i got looks pretty much the same though. i think the problem is that there are no slots/holes for air flow on the 510 side of the adapter. i can get vapor when i used it, but it was worse than sucking through a straw.
ahh....I know if you adjust it the center posts on both ends will move outward...the slots are in the battery itself and ...adjusting it the adapter ends up not sitting flush....but you don't need airholes in the 510 side of the adapter...there should be a couple of airholes in the 909/808 side of the adapter...so with those airholes, the slot in the adapter, the slots on the carto you should get a ton of airflow...