As far as we know, there is no GM-made UIM for our cars that has completely resolved the possibility of failure, yet. So, you will have to pay attention to your car and be aware that you may still have to do this repair again.
The best UIM replacement products out there so far are the Dorman kits and the APN kits. These both include heavier walls and reduced diameter stovepipes for a more likely chance that failure can be avoided, or at least delayed a lot.
Also, in 2003, the New style aluminum-framed LIM gasket had not been release, so you will still have to keep an eye on that, for now too.
Mike: 1997 SE w/ 183K, aka White Horse
, Gutted Airbox w/K&N, drilled 180* t-stat, tint all around, clear corners w/SilverStars, "PONTIAC" light up tail, PEMs, NGK TR55s