They do do work. But I believe they have a bit of a waiting list. Just replace seals and try if I was you :)
I believe they do internal work, while I have not gotten this service personally, I've seen other customers getting aide with their AEGs. I would only assume they also do work on GBBs.
Yes they do the also do upgrades and updates
Yes, if they have the parts. But if they don't it takes longer because they have to order them.
They repair. Might take a while though. Make sure to ask about time and details before committing.
They absolutely do repairs, service, and upgrades. They can have a waiting list so keep that in mind, but I've also found their prices for service fair, and their recommendations spot on.
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