I'm another in the camp that a knee mill is a far better choice. As for brand, Bridgeport is the one all others compare themselves to. They were the first in the field and by far the most common. There are a lot of other quality brands out there, but I'm not sure what support exists in the form of replacement parts or knowledge on repair procedures is concerned.
Personally, I wouldn't limit myself to a step pulley head, and I would avoid machines with the smaller 36" table. I would opt for either a 42" or a 49" table. I've had a Series 1 variable speed head machine in the shop well over 20 years and haven't needed to do anything but normal maintenance like cleaning and oiling. Even if at some point in time the head might need some work, they aren't that complicated, and parts are readily available. Places like H&W Machine Repair (
https://machinerypartsdepot.com/) have kits available at reasonable prices, and they are more than happy to walk you through the process.
As for the time to find a quality machine I spent over 2 years and literally looked at hundreds of machines. I was originally looking for a Tree brand mill because those were the ones we used at work. I liked the size, rigidity, and features. Unfortunately, all those I found were either well past worn out, or way out of my budget. After a considerable time limiting myself to a Tree machine, I decided to expand the search to include other brands. The Bridgeport I finally purchased came from a local high school. It was in excellent shape, and had both metric and imperial dials on all axis. As Mathew mentioned shy away from those that have been used in a production situation. Those from job shops, fabricators, and schools are more likely to be in good shape.
As for chromed ways they are hard enough that flaking will exist for many years. MY mill was built in 1972. It doesn't have chrome ways, and the flaking is still visible in the area shown in your first post. That's usually the last place for it to wear off since the table isn't generally extended that far. In a production environment the machines are commonly setup to perform the same or similar procedures day after day. Wear is generally in one section of the X axis, and one section of the Y axis.
One thing to look for is a 1 shot oiling system. Oiling the head and table is a bit of a PITA, and it's hard to remember when it was last done unless you have a written maintenance schedule. Those without the oiler are far more likely to have wear issues due to lack of regular lubrication.
As far as price is concerned a used Bridgeport in good condition usually costs less than 20% of the list price of a new one, and around 30% of new offshore machines. In my opinion a used machine in good condition is far more cost effective for the hobbyist than any other option. Keep in mind tooling will cost at least as much as the machine, and depending on what you're doing may cost far more than the machine. Used Bridgeport tooling in good condition is far more common and far less expensive than tooling for most other brands.
