I've noticed this from day 1 on all 7 of my Mod1 rifles... the engagement feels very weak.
I figure it is the spring being too short or something so I decide to cut a piece of O-Ring that will fit inside the PG's detent spring hole, to increase the engagement tension on the safety.
It works pretty well, and the 'snap' definitely have improved...but it is still not as 'snappy' as my Colt, Spike, PSA rifles or my friend's S&W, BCM, Aero.
Even if I make the engagement tension stronger by dropping in a larger piece of O-ring, it is still not 'snappy', but definitely increased the friction/engagement tension.
From my experience, the 'lack of snap' is due to the design of the safety detent hole, or something to that nature, as the spring tension didn't exactly 'fix' the issue.
I think the size of the detent hole might be smaller, or the angle/slope of the hole might be steeper and less wide, causing it to be less likely to contact the detent sooner.