I own a cts2 and recently puchased a 97 cts. There is not a lot of difference between the two combines. The cts2 has more rated horsepower, has a digital concave and a number scale on the sieve adjustments, and has a different concave. However, I found that all the older cts combines were sent back and the power uprated, so there is not much difference. The digital concave and sieve adjusters is nice, but it makes you lazy and not take the time to set the shoe for max capacity. Most cts have the hopper topper on, so hopper size is probably the same. Make sure that the combines do not have the fine cut widespread choppers on them. These choppers consume enormous amounts of power and the hammers wear out quick and are very expensive to replace! Some of the older cts combines did not have dual range cylinder or dual speed beaters as standard equipment. Also, the tine separators can be ordered with 500 or 700 rpm drives, and depending on what you are combining, each has its place.