I know this is late and maybe doesn't matter anymore but I just joined and saw this. My dad had a 1975 Columbia 45 that he bought in 1977 and kept until he passed in 1996. I logged thousands of miles on it and it was the boat many people sailed for the first time, so it took a beating.
Based on what I'm reading here, this boat should have been built in 1973 (maybe it was and my memory is fading) because this thing was built like a tank. But it was slowwwww, especially in light air.
What it lacked in speed it made up in comfort. Huge aft cabin with private head and separate shower, great headroom in the main saloon, air conditioning and comfy seating and sleeping. I slept like a rock on that boat.
We took it the 330+ miles up and down Lake Michigan many times and we hit some very rough conditions. The worst was a steady 30 knot wind out of the north that brought 12 foot seas. One time we pounded into 5 footers, motor on, for 15 hours to meet my dad. The boat held up, I was beat.
Due to its short mast, we hardly ever had to shorten sail. You could get 6-7 knots out of it in good wind, if you're heading in the right direction.
I can't remember any leaks. We never had a catastrophic failure. We bounced off rocks more times than I care to admit. My dad beached it in the Bahamas once. And he wasn't the greatest when it came to regular maintenance.
For what my dad wanted, it was perfect, a boat that had creature comforts and could take a beating. But if I was looking for a world cruiser, I'd look elsewhere.