Forgive me for jumping in, but
I had all the very same problems, but now the LR 306s are my favorite atty...
The covers all full length--unlike the 510, so you have to screw them on your Phidias (don't have one? get one..lol) in order to pull the cover off...
that's one mystery solved
The black drip tips are a perfect fit---however, they need to be heated up to assume their proper size.
2 mysteries solved, none to go...
Put one on, leave that space, take a few hits and it'll slip right down, just as nice as can be....
The things are so unlike the other attys that they can stump even the most experienced vaper---
Heck I had to have drew walk me
through my first 306 installation... I felt like a newb
You really do feel silly once you see how trouble free the whole thing is...
LR 306? got-a love them
Best Regards
fo