Personally I'm not a fan of the Chinese machines. I've used a few in my day, but they were disappointing experiences compared to the US made iron. I do own a Bridgeport, but again it was not originally my machine of choice. I was originally looking for a Tree brand machine, specifically the 2UVR model. We had several Bridgeports, and Trees in our shop, and the Trees were by far the easiest (for us short guys) to setup and use. Changing tooling was easier, and the Tree machines seemed more stout and less prone to vibration.
That being said I looked for over 2 years for my first mill and found every Tree machine on the market to be either wildly over priced, or worn to the point it would have taken more time and money to refurbish than it was worth. In addition I found the tooling to be far more expensive and much harder to find.
One thing I did note throughout my search was that machines that appeared to be run hard and put away wet generally reflected lack of attention in their state of repair. Those covered with dried cutting oil, filthy oil and grease fittings, and covered in chips showed far more wear than those kept clean and regularly lubricated. On the other hand those with no signs of having been used, and sporting a fresh paint raised red flags as to what the condition of the machine was before the new paint was applied.
I almost put purchasing a mill on the back burner until someone alerted me to one from a local high school that was sold at an auction. The buyer bought it as part of a lot and was only interested in keeping another machine in the lot which happened to be a Clausing lathe. I contacted the buyer and went over for an inspection. What I found was a mill in reasonable condition for a reasonable price. There was about .030 backlash in the X lead screw, and .020 in the Y lead screw. The table didn't bind throughout the length of travel, and did not get tight near the ends. The variable speed head was quiet and would easily shift from high to low range, and the auto down feed worked properly. About the only problem I found was that the ram wouldn't change position regardless of how loose the retaining bolts were. After an extended period in storage the ways on the ram had rusted to the point the head wouldn't move. About a weeks worth of daily doses of penetrating oil finally freed the head.
Digging into the history of the machine I found it was originally purchased by the high school in 1972. It was in their machine shop until about 1992. At that time it was replaced by an early CNC machine and sent into storage. In 2002 the school district deemed it to be surplus and was auctioned off at that time. Essentially it sat for 10 years in a store room. If the machine is being sold by the original owner they should be able to provide some history. If it's being sold by a vendor they should know where it came from and what type of work it did.
I guess my point is that a relatively thorough inspection will needed on any machine you are truly interested in to be sure the machine will be "reasonable" condition. Many can be dismissed due to obvious lack of maintenance and operator care. Patience and perseverance are the keys to finding a good machine at a reasonable price. Don't be fooled by a machine that looks shiny and appears to have little or no wear. These machines were purchased to work on a daily basis. If the normal wear parts like crank handles, feed levers, and adjustment fasteners don't show some wear proceed with caution.