Re: Lawn tractor fo 3+ acres
I'm in mid-Michigan, so I am almost the same weather conditions as you.
The X740 would be the way to go out of the 3 choices, definitely not the LT-type units as the are just lawn tractors. Not saying anything is wrong with the X540, I have a 2010 X530 (w/400 hours) and a 54" deck and it takes me 2 to 2.5 hours to mow my 3 acres. You do not want to be doing it with a 48" deck! I sometimes wish I had a 60" deck, but I don't have a totally flat yard and have a ditch and pine trees on a mound running the front end of my property and a larger deck would be tough to mow that area. As it is I notice a bend in the two hanger mounts on the deck from it leaning to the left side as I mow the ditch. But that is my yard.
I have the 47" snowblower on mine, it makes quick work of my 200' cement driveway and turnarounds. I tried running just the 4 suitcase weights on it with chains, but last year went with 50# rear tire weights and 2 suitcase weights and chains. That worked very well and I think I only got partially stuck once when I went too far off the driveway down by the road and had the machine pointed slightly downhill. It's a snow eating machine, much better than the 2-stage walk behind I brought with me from the city. I like clearing snow now.
For the cost part, I can't say if those are fair prices or not. I paid $5400 for my 2010 X530 four years ago with 200 hours, and it came with the 47" snowblower and tire chains, spreader, and aerator. I have no regrets on buying used, it was the only affordable option after buying the house. I tried mowing with the LT166/48" my dad loaned me (so he could buy a new X300 series) and it was taking me over 3 hours with the pedal mashed to the floorboard as much as I could. I did that a couple of times and knew I needed to go up in machine class and I found the X530. Good thing, the LT died soon afterwards when it went to my uncle's place.
Sometimes I wish I had an X700 class, I've read they do have a little better cut quality than the X500 series. I dream of having the CUT series, but even used they are way out of my price range.
Hope I have been of some help in your decision.
2010 X530 with:
54" Mower Deck
47" Snow Blower
40" Tractor Shovel