Chainsaw Repair

I have feedback on the 2 different styles of stihl flippy cap replacements. By end users.

LCS one sometimes gets tight or awkward to remove. Locks in place and has push button unlock. I think it could be forgetting to unlock it.  Better grade of plastic used IMO.
 O-ring prefect shape no leaks. Have to be modded the Y  part on string to use in the stihl oem location.  The string slide in part in tanks. They come with Y on end.

CCC one Easier to use. Dont lock. O-rings c-racked all the way around even new unused.  Worry about the cracks in O-rings breaking through and leaking.   Come with the right oem string attachment for tanks.
Inoperable sometimes with E10 and become harder to turn because they swell up.  Maybe the type of plastic use?

I will use either one at saw owners decision.  I like having both of these as a replacement option.

Still waiting on the small ones to come out as I have request from homeowner saw owners. LCS has them in the works.

UPDATE: No small ones. Idea shelved.