I've found Giant to be very reliable - I still have one that is 15 years old and after a swag of crashes there is still no sign of cracking
My Giant TCR carbon road bike was brilliant, and still going under someone else. I doubt it will ever break. A business partners has a CFR and he has had that for a long long time, and unless he throws it under a truck it won't break. I think Giant makes very good bikes.
Both frames replaced under warranty to date were welded metal frames, and
**** on the driveside chainstay near the bridge between the two chainstays. I suspect each failure was a result of a slightly less than perfect weld (much harder to weld Ti than Al) coupled to a fat bunter riding with at times less than perfect technique. If I weighed 60 kg I suspect neither frame would have failed. If I weighed 60 kg I suspect I might be quicker up hills but slower down them.