Does anyone used these Gunnebo Chain Couplers?

I purchased my new Maggi chain (5/16" heat treated) with one on each end - had to cut one off since it wouldn't fit down the hawser - let alone feed in the windlass!
They look exceedingly robust - significantly stronger (I hope) than a standard shackle - always the weak link in the rode - but I wonder if anyone has any opinions/experience with them?

They are held together with a pair of coiled spring pins (I ended up mousing them just to be sure) - is this a weakness?

Appreciate any thoughts...


(This is the extra one - pins partially pushed out - was trying to see how easy they come out - NOT easily!)


Bill Balme