Goalkeeper or Goalleaker?

[nikolgiorgos]

yes
The general quality of a player matters (in 1-1 duels), as the contribution in team's gen. quality, as in the bar of defense (when comparing two teams), as the % of success in opponent's free kicks.
So it affects the calculations.
But if you replace a 5* GK which you believe is good (or bad) and reliable with a 5* GK you just bought from auctions, it won't make any difference.