A few years ago, one of my temp sensors failed. It was a cold Sunday morning and I was on my way to church. One of the small coolant lines blew and I saw steam in my rearview about a mile from my destination. When I arrived I knew I had a problem since steam and coolant were everywhere. After new hoses and t-stat, I continued to run hot without a fan all week - it was a below zero week though, so I got away with it until I figured out that the sensor was bad.
Never had that kind of problem again, but my fan doesn't come on until about the 65% spot on the gauge and my temps seem to run hot most of the time. The Thursday before Memorial Day weekend it was hot in the afternoon and I ran the A/C. It ran high on the gauge just out of the red and I smelled a little A/C clutch, although everything works fine still.
I will check my fins like suggested, and consider a different intercooler when I replace the Turbo soon. A bigger double-core radiator is a good option as well, and there is a recent post covering a better electric double fan assembly now available. The gauge on these cars is suspect, as the oil pressure gauge
BTW, we should get together sometime, I live in Allendale.