Yes, I didn't mention the 175...but my Dad puts both the 175 and 180 in the same "stay away from them" category. I really hate to mention this since I've had no personal experience with either of them...but these two models have a bit of bad reputation around our part of the county.
My Dad owned a 150 for a few years and now has an IH 684. He's always said the 150 was the best tractor he's ever had. He always maintained that he could run it all day and not use a tank of fuel.
I can more easily find older Ford tractors around here (like the 3000, 4000, and 4600), but they are usually a bit more expensive especially if they've been restored to any degree.
I have a 52 Farmall Super C with wide front, new tires, 12V conversion, and 3-pt conversion which I need to sell. I bought it to use, but Dad insisted that it is just too clean to mess up. The old Farmall is just tough as nails...not much you can say bad about them.