Awesome! I had a 1999 with 75k miles on it. I did have problems with it, mostly electrical. I just think at that time those cars were a little ahead of the curve - at least electrically - and GM hadn't ironed out the bugs yet. In the short time I owned mine I had traction control problems daily...I don't think I made 10 miles without some sort of light going on. The head light motors strip out. The steering wheel lock is magnetic and when it breaks...and it will...you will be stranded. Mechanically the harmonic balancers go bad on these cars and it's a pain to replace.
But the 5.7 is a reliable motor, gets decent fuel economy and has loads of power. Amazing to see someone get over 600,000 miles on one.