★ LS430 FAQ (Frequently Asked Questions) and DIY Thread ★ - Club Lexus Forums
Not entirely familiar with the LS430, but when I was looking into one, I found a few things that might be a "rpoblem"
With the UL(Ultra Luxury) Package, the Air suspension is expensive to replace. Somewhere around $1k a corner.
Car develops a creaking sound at high mileage, which can be fixed by torquing down the steering rack and subframe.
From what I've found though, the LS is over-engineered twice over. Other than mileage and expensive parts, they shouldn't have any problems with it as a daily driver.