I've spent most of the day scheming and browsing the internet for ways to use the 3PH. I have thoughts of converting my leaf vac to 3pt (the 2 swivel wheels are hard on the lawn), and am considering the Omni Transformer with weight bracket and carry all basket. I think it will become a permanent fixture on the tractor.
JDTank, that is why "inferior" was in quotes. I'm sure the older decks work just fine. I just kept reading complaints about cut quality (from some) and how much better the new ones are w.r.t. cut quality as well as beef. I was torn between x749 (diesel and lesser deck) or wait to 2013 for the X739 (better deck and no diesel). Decided I didn't really need the diesel for mowing and snow removal (and timing wasn't ideal either). My current gasser has never left me wanting more power for those chores and with 5 more HP on the x739, it will do all that I need it to. Besides I have a diesel beast in my bigger tractor when I need it for work requiring serious torque/power.
As for running a cold diesel with a mower load, you can do what you want, but I wouldn't engage any PTO implement onto a cold diesel. I don't care what the owner's manual might say. And I probably won't be so quick to do it with my new fuel injected tractor either, even though they claim it's OK. I like to warm an engine before loading it, and in cold weather that can take a while with a diesel engine. I ran my Kioti on Saturday. It was about 34 degrees or so. It took a full 10 minutes to reach full warm up temperature. Of course, I did start out at idle and gradually increased RPMs over the 10 minute period. At idle, it probably would never reach full temperature. My 425 gasser warms in about 1-2 minutes at full throttle. That's probably how long I will wait with the new tractor too. I also "cool" my engines by running at idle for several seconds before shutting off. I've had good luck with this approach. The 425 is 20 years old, starts and runs like new, burns zero oil. May run for another 1000 hours.