TC40 is a Shibaura-built tractor. I am a huge fan of Shibaura tractors dating back to the Ford compacts of the late 1970's. The TC40 is a great machine. If the machine you are looking at has a loader, hst and super steer, it is probably priced ok - maybe a little high. Without those features, it may be a bit on the spendy side.
The WM 37 is built by NH with a Shibaura engine. It will have Tier 4 emissions and the associated downsides.
Looking at specs on tractordata.com, the TC40 will lift around 500 lbs more at the 3 pt. Also, the TC40 will be heavier and quite a bit larger in person. The WM37 has 11.2-24 rear tires and the TC40 will have 14.9-24 rears - that's a substantial size difference. Loader lift advantage goes to the TC, as well.
I believe that the TC40 is much more tractor than the WM37, and I would buy it over the newer tractor. The 2 grand savings is a bonus.