Ben Affleck -- Good Genes or Good Docs?!

Ben Affleck's good looks are major Deja Vu.

Here's a 30-year-old version of the movie icon making an appearance at his then-girlfriend Jennifer Lopez's restaurant opening in Pasadena back in 2002 (left). This was the same year the Hollywood power couple worked together to create the classic 2003 rom-com "Gigli."

And, almost 20 years later the father of three ... who is celebrating his 49th birthday today ... has rekindled the twosomes courting status and was photographed earlier this week smiling for very obvious reasons (right).

Ben's been making the most of his birthday month alongside J-Lo with shopping sprees in Capri, Beverly Hills date nights, 85 million dollar house hunting, fine dining with fam at Craig's and even hanging out on set.

The Jen-efits of true love.

The question is ...