I liked Akagi more than Kaiji simply because Akagi was GAR and that overwhelmed me emotionally, that and how detailled the logic in the mahjong games were (after learning the game, go back and watch the anime again and everything is actually well thought out) made it an exceptionally well written story IMO.
Kaiji is a better gambling anime and a better written story though - all around, it's one of the best anime made, but in terms of delivering one thing (psychological thrills) it wasn't as adept at it as Akagi was.
Some of Kaiji's logic and the events were also weird, a product of Madhouse animation. Like the magic staircase, which was plausible but as depicted in the anime really weird. Also when Kaiji makes assumptions was also moments of weak plot.
The final arc in Kaiji was actually the best IMO, Tissue Box Raffle.
tl;dr - both are good, like what you want, but we can agree Fukumoto is a fucking amazing manga-ka and Yuuji Sato a great director.