Ive had zero failures with Ivoclar multilink Implant.
You must blast the Ti and Zr and apply Monobond Plus first.
Im of the belief that you shouldnt do it 'in hand'. I always seat the Ti in the model and then bond. Otherwise you introduce a slight variable. I was contacted by a Dr for help with a case he sent to a 'top lab' in California. Big bridge, non-engaging inserts. When he seated the bridge, one of the inserts would pop out. Returned to the lab, came back and same thing. Dr was in a panic. Simple solution...the inserts were still shiny.
I got them all debonded and cleaned up; screwed into the model, the bridge had a slight rock. I made a very small adjustment to get it down and bonded it in place, on the model. Dr said it worked great.