perin as a shot stopper is actually very underrated. in his 6 years at juve, he's got a higher save% than tek (79% vs 75% iirc, should check), and statistically he's better at saving more difficult shots too
as
@icemaη says, it's the passing that stops perin from becoming a top shelf goalie. perin's launch accuracy is well below 40%, for tek it's around 50% iirc. and that's a huge difference, even if you don't want to have the ball
also tek is kind of a leader. he's more vocal and can better organize a defense. and of course tek is better at saving penalties