Maybe not its just maybe im not used to the feel of the bigger o ring. I will try to find slightly smaller o ring and check if it will help. Im just wondering if they change o ring size on my batch of light.
Same thing happens with mine. I’ve reapplied super lube and changed to the additional O-ring provided, but it still binds. I’m currently waiting for the O-rings from fasttech and will see if that helps at all.
Ordered and thanks 
The o ring will usually pop out thru groove running parallel to the light. The gooves runs thru the o ring canal. I cant compare it to my group buy Q8 because I misplaced it. By chance if anybody can check if they run thru the o ring canal, please! Thanks :+1:
If I understand what you are saying/asking, I can verify that my Q8’s have no grooves running into or thru the “O-ring canal”.
Is your O ring in this position?
It seems like they should cut the o-ring groove just the tiniest bit deeper. You could probably take a hacksaw blade and gently go around the groove and remove just the tiniest bit. Maybe just removing the black finish is enough. The head only needs to squish the o-ring a tiny bit to form a waterproof seal. I’m guessing it’s squishing it too much.
Let that hacksaw solution be your very last resort. 
Something has changed or is out of whack with yours. None of mine do that.
Is your o-ring in the position shirnask pointed out in his picture??
Yes.
And the o ring squeeze out thru that groove perpendicular to the o ring. All my 3 Q8 are doing it. Im thinking maybe they use slightly bigger o ring this time. Just my thought :weary: Just biught it from BG US warehouse.
Well then the fasttech O rings are probably the best ansewer.
Hopefully, it is. If not; I fear the the last resort: hack saw :person_facepalming: I hate to mutilate a beautiful and perfect light 
Mutilate? It is just a poor man’s CNC machine. Lol
Add a little black marker to hide the raw aluminum and you won’t even know. Plus it’s completely covered by the head when together, which is 99.9% of the time.
A needle file might make a smoother cut, but not everyone has them.
All the control modes and functions are focused on a single switch, and I'm worried about how long it will last with a high lifetime of frequent clicks
You can get a replacement switch assembly from the Sofirn store on AliExpress for about $2.98
Yep… here is a link in fact. Go ahead & get you a spare or two while the getting is good. I sure did…. 
$3.01 is the latest price it seems.
https://m.aliexpress.com/item/32879434650.html?trace=storeDetail2msiteDetail
By the time the switch would wear out there would be a whole new Next Level of Technology flashlights. Lol
I’m pretty sure the switches are the usual cheap ones and I replaced a couple of them in different lights meanwhile (not Q8 up to now).
Just received my Q8 via Amazon AU. Oring problem here too. Reapply grease to no avail. Has fasttech orings helped?
They worked just fine to replace the damaged O ring on one of my Q8s - but the original worked well until I messed it up :person_facepalming:
If the problem is not the grove that the O ring sits in they should fix your problem