Wales great Southall believes the Spaniard, 30, who moved to Anfield from Villarreal in 2005, has proved himself a level above his counterparts at other clubs in the top flight.
Southall told the Daily Star Sunday: "If I had to sign one Premier League goalkeeper, it would be Pepe. Even though he's had a dodgy start to the season, I just like the way he plays.
"But if I was a young goalkeeper looking to study someone, I'd tell them to look no further than Pepe. His distribution is so good and so comfortable - and his first thought is to always attack and be positive.
"Pepe has made a couple of errors but he always makes a few during a season. Every goalie does.
"If you play for a lesser team it doesn't matter but because he plays in a city like Liverpool - it does.
"But he never hides. He's positive every week and that is the best quality of a goalkeeper.
"You will mess up now and again. That's just the job. You're only as good as your last save but Pepe always bounces back."