I remember having bought the game during Christmas 2002, but being so disgusted by that filthy brown goop being thrown everywhere that I never got pass the first mission ! I was pretty young back then.
Three years later, I mustered up some courage and gave it another shot.
And well... it was pretty good. Not awesome, not masterpiece-level, but pretty good. It more of a 7 to 8/10 game were 64 and the two Galaxy games were solid 9's, even 10's.
Some levels like the theme park were great, while others like the mansion were a tad boring. The pure platforming levels were horrendous, and I dreaded them everytime they appeared. And man, some bonus levels like the flipper one were broken beyond belief. Considering Nintendo's QA standards, it was pretty baffling.
But like everyone else, I loved the tropical setting, the soundtrack, the graphics (I am still bummed it wasn't 60 fps though), and the "story" was a bit more fleshed-out and interesting than the previous entries. The whole doppelganger thing with Antimario and Peach being not captured from the get-go were nice breaks from the formula.
If you haven't played the game yet, just stick to the main quest. This is the only 3D Mario game where doing the 100% route is not only unnecessary but will only degrade the whole experience. The is the COMPLETE opposite of Odyssey !