Hey Lenders, why don't we play a game? We both place calendars of years after 2008, close our eyes, and point to a random day in that year. And then we do that for 2009, 2010, 2011, 2012... and onwards. On that day, that's when Tsonga plays unbelievably well. Otherwise? Some flashes here and there, but face it: Tsonga never had the potential to threaten greatness.
He was a flash in the pan, through and through. Why do you talk about who is overrated by the forums? That's clearly Tsonga. Because his game is flashy and big (when on), he seems like a chill person, and there are absolutely no subtleties to his game. Ferrer on the other hand is widely viewed not as a slam contender, but as a great player who doesn't think he belongs at the top.
From the locker rooms, players know Jo as a bad loser. Now why is that? It's because of his inflated ego, fueled by his eons of fans who tell him the same thing. They tell him that he is too great not to win a major. Tsonga is a ponzi scheme. Every player and every fan gives him a slice of the pie, and for what? Tsonga was always hot, cold, hot, cold, hot, and motherfucking cold. Tsonga has huge weaknesses in his backhand, and ROS. His defensive skills aren't very good either. When he's hot, those weaknesses are temporarily hidden. When cold, it looks like Tsonga never tried to begin with. That's why everyone is still in denial about what happened in RG in 2013. David crushed him thoroughly, exploiting those weaknesses and drawing error after error, while hitting many winners himself. David humiliated Tsonga thoroughly, and fairly.
Now am I saying that David is greater than Tsonga? No - the stats indicate otherwise. What I do say is that while Tsonga gets hot, he only ever had the potential to win one slam. Forget multi-slams. He is overrated because of his offensive weapons and personality. Another overrated player is Berdych - once again the fans are blinded by offensive weapons. Berdych doesn't have enough weapons to win slams, because he can't change direction on the ball when pulled wide, he's too slow, defense sucks, etc.
As for the answer to the topic, it depends what you mean by "better". At their peaks, David would easily have positive H2Hs against Tsonga in 3/4 slams. Tsonga is more accomplished than Ferrer. Both are great players and both never had the potential to be all-time greats.