After many tries at snagging a LaCrosse from Alamo or Avis for a weekend, I finally succeeded. It was at the Alamo location at LAX. Interestingly enough, I had just taken a Friday off in Las Vegas where I had a Grand Prix, so I got to test them back to back.
In short, I used to drool over the LaCrosse. Now, it's just a nice car. Chief among my disappointments was the purported quietness. Maybe this only applies when equipped with the 3.6 VVT V6. With the base 3800, the engine roar is just a tad quieter than it is on the Grand Prix.
I took the LaCrosse out to the desert and back as well as all around the West side. The ride is fairly controlled yet pavement gaps do cause some undulation -- Buick style. It is not a tight riding vehicle. In terms of cornering, it does so more flatly than its predecessor but still does not beg to be pushed. I noticed this in the cloverleaf exits from the 405 onto Wilshire Boulevard.
It is a nicely appointed car. The instrumentation is clean and (as Paulie always questions) it's illumination is green at night. While the Grand Prix groups its chimes and warnings more succintly, the LaCrosse has a zillion little indicators in the instrument cluster. It was almost distracting.
In terms of ergonomics, the seating up front is comfortable and the flatness of the buckets allows one to move over to reach things. The flatter panel gives the illusion of roominess, but it would be no easier than in the more cockpit like GP to crawl over the console and get out.
Now, the Buick sports the glassier greenhouse. However, this works best for vision over to the rear passenger side of the car. In changing lanes to the left, the doubling up of the pillars to make for that little opera window make it a challenge.
The LaCrosse is a clean, safe car in terms of its exterior sheetmetal. It won't age quickly. However, I just saw the new Lucerne last weekend. (Kudos to Buick for a leapfrog over the LeSabre/PA, but it's too big for me). However, I will have to say that the crisp, canted angular grille would work wonders for the LaCrosse. In comparison, the LaCrosse's front end styling approaches the "frump zone."
This is all very fresh since I lived in a Grand Prix the preceding day in Las Vegas. The GP's big liability is the overstyling...particulary in the front. It is, however, much more of a driver's car. The handling inspires confidence and it does what is asked of it. Smoothness at cruise and the sense of quiet (when the engine is pushed and via wind intrusion) are not markedly different from that of the LaCrosse. And, with the split exhaust pulled out of the base model, the exhaust burble (or fart) that I found offensive in the 2004 is a more subdued and more even exhaust note. But, when one hits the pavement joints and freeway ripples, GP reacts crisply and stays composed. The dashboard, while quite different, is a pilot's domain...you really are in a cockpit of sorts.
All in all, I think I would opt for the Grand Prix. I like both cars. It's just that I like the GP more. Now, if the LaCrosse spruced up the front and made it more angular while the GPs stayed the same, I would pop for the LaCrosse. If the converse occurred whereby the GP got rid of the "Smokey and the Bandit" pinched fascia while the LaCrosse kept its chromey oval, I would go into the GP with that much more enthusiasm.
Either way, proven "old school" platforms and cast iron 3800s can't be argued with.