I just got my second Terminator and noticed it has a different center pin. The air hole path is smaller and makes for a very slightly tighter draw. You would never even notice the difference if you didn't know it was there, but it seems to have changed air/vapor mixture some. There is more TH now with about the same vapor and taste. Once this coil is spent I'm going to make a new one and use the same juice in both to dod a side by side. Once I get hole I can take some pics.
Just redid mine this morning, switched from a single coil / dual wick to a dual coil / dual wick X config, with a small piece of silica sitting under the top coil. So far it seems to be doing pretty well.