I've had best results with the 24hr. stuff, the 5min stuff tends to be on the brittle side and doesn't give as strong a bond as the 24hr stuff.
Has anyone used a 48-72hr epoxy? If so do they seem to work much better then a 24hr?
I've never seen anything longer than a 24 hour cure epoxy. The HIT 2-part epoxy works great, never had an insert come loose using it.......even trying to knock them out. Some of the general stuff on the market I've had HIT's break free on hard hits.
My Golfsmith 2-part epoxy has worked well too. And obviously it's "impact" resistant as it holds up to all those swings and hard hits on the clubs. I've never had a club head come off unless I was taking it off.
Carbon Tech's "Rick's Glue" is a 48hr epoxy. Mammoth sold by bishop archery is a 72hr epoxy. I don't know much about them, but would be curious if they work better then a 24hr epoxy.