I have been very happy with my TC40D. I find it to be a very capable unit. It has done just about everything I have asked it to do.
Fortunately (thanks to this site) I did all my research BEFORE buying, so I knew what problems to expect. In fact, just about everything that has gone wrong with the Class III boomers has, in fact, happened to mine. But, I knew what to look for and how to fix/work-around the issues. My expectations were set and have been met or exceeded.
My dealer has been very good - this being said without having had warranty service done since I've owned it. I did have them do some warranty work and modifications BEFORE I purchased it (it was slightly used - 6 months, 31 hours) and they did all of this very competently. I have spoken to my salesman several times since taking delivery and he always seems happy to hear from me.
All my implements that I bought are used, except for the front end loader - for all around use, I couldn't see owning a tractor without one. The quick-attach bucket and pallet forks are a dream-come-true for my needs. In fact, I use the forks more than the bucket for moving hay bales, logs, stumps, and firewood (I palletize it now). But when I switch between the two, it takes less than 30 seconds, including hopping off the tractor to latch and unlatch the two levers.
I am surprised by how much I like the HST. I was pricing new units and specifically wanted a shuttle-shift - I hated every HST I drove and I drove them ALL. But, my dealer and I negotiated a price I couldnt walk away from and I figured I could learn to live with it. Now, I wouldnt want to have a tractor without it. The biggest benefit I find is safety with loader use - I can creep to the edge of a ravine to dump brush, have one foot on the brake and the other building reverse pressure without ever disengaging the drivetrain (kind of like the Subaru Hill-holder Clutch.) Plus, with the precision loader work, like picking up pallets and large log sections, it is easier to creep forwards and backwards for me. I probably wouldn't miss it if I didn't have it, but it's nice.
I haven't used any PTO attachments yet, so I can't speak to PTO brakes, but (being forearmed with knowledge) I'm going to be cautious with my use.
In sum, I would buy my tractor all over again. I would have had a couple things done before it came home - cooling bypass, thermostat modified, and auxilliary FRONT lighting (headlights are almost useless with FEL). But, yes, I feel I made the right decision for me.
Mark