Those are generally for DTL vaping. But some use them for MTL by closing down the AFC. The Crossbow MTL rba by Kindbright is just for MTL. I've seen them at:Can any of these be closed down enough for him to MTL on them. No problems with the building as I can do that with no problem. Any input would be gratefully appreciated.
Here are some inserts to restrict the airflow down enough for MTL. Unfortunately they don't say for which RBA they are for. I know people were buying inserts like these to convert VapeShell RBA for MTL vaping. Might be worth picking up if you have a few extra bucks to spend for some of the other RBA you mentioned.
While one of the DTL RBA is the Insider. I probably should mention that I have seen a rare Insider MTL Edition. But its authentic and cost $150.