Ran into my local. He said what bother shim is the use of Briggs and Stratten engines so he only recommends the CDS and says its a great unit. He said if he had to choose a slide in he'd use the Boxxer XL. Not familiar with it though.
To be fair, we see a large large LARGE number of HydraMaster units in this area, of all shapes and sizes and conditions. The B&S engines functionally don't seem to have any more problems than the Kubotas do, as long as they are maintained properly and aren't under max demand all the bloody time.
The problem is, when they get neglected (as many do), B&S are a wee bit quicker to complain and have temper tantrums than other brands. So I'd say the problem inherent in those engines isn't exactly the engine itself - it's just that they're not built with a particularly large margin for neglect.
And a lot of guys buy smaller TMs due to cost, then push the units to perform at max capacity for extended periods of time. Save money up front, lose money over time in wear and tear on the unit. Kinda like running your Honda Accord at 110 mph every day because it says you can on the tach.
As for resale value - that depends as much on how well the machine is kept (is it clean, does it run right, has it been maintained?) as on what kind of machine it is. If it's in a raggedy van with rusted-out fenders and a bungee cord holding the door shut, prepare to get dickered down hard. Current models should retain their value well, as parts are immediately available across the country. Discontinued models may be a harder sell.
Being heat exchanger units, you're not going to get 280 degrees out of them, so don't try. Even the Titans max out at 265. Vacuum, however, they perform very well - I watched an XDrive just about yank a guy's pants off when the hose flopped too close to his leg.
Overall, I'd say the HMs are less "froo-froo" than Legend (Sapphire/Prochem) but very functional, durable machines when taken care of. We see the bad side of ALL machines in our shop. Balancing the number of HM repairs with the number of HM units running in the area, their total breakdown ratio is very low indeed.