I have a x534 with a 48" deck which I bought in 2010. I also bought at that time the 47" snow blower, a pair of 42# suitcase weights, and the 7 bu. power flow bagger. My x534 now has close to 150 hours with no problems to date and all regular service completed by me.
I love the power steering and deck lift. I wish there was a little more range in the lift for raising the snowblower. I've adjusted the lift a couple times and can't seem to get it more than 4 inches off the ground. I would like to have a little more clearance, say 6 inches, but other than that the 47" blower is the best. I was considering a walk behind at the time but the 47 was about the same price and one less motor to maintain. Mount/dismount only takes a couple minutes. Get the tire chains. I did when I ordered the mower and snowblower and the first winter I thought "I don't need no stinking tire chains" but then it turned out I did and I was glad they were in the garage in the box. I slipped them on and a huge difference. Two winters later I dumped the chains in favor of the Terra-grips because the chains tend to mark up you concrete and asphalt. The terra-grips have been working great the past two winters. If I had it to do over I would have ordered the Terra-grips from the get go for my situation. I like the AWS when snowblowing as I feel it puts the thrust in the desired direction of travel in contrast to front steering only where you are trying to redirect the thrust by turning the front wheels.
Be sure to get the weights (looking back I should have got four), you need them to counterbalance the snowblower and get some traction, your fat arse alone will not be enough, my 215# surely isn't.
The power flow bagger works very well, never had a problem unless my cuttings were a little too long and damp/wet, then when the bags get full the grass will tend to clog in the chute due to reduced velocity but that's an operator error not the fault of the machine.
Every time I get on the machine I want to disable that darn reverse switch, and then I think better of it.
It is a PITA yes but you get used to it, or maybe tolerate is a better word to describe it.
I keep thinking of all the people I see mowing with the deflector chute tied back and all the clippings flying out of the mower along with whatever else the blade might come in contact with and launch my way. I believe defeating a safety feature is just crazy.
I can picture myself on the witness stand having to explain why I believed I knew better than the couple dozen engineers who designed and tested the thing. Inadvertently injuring someone or even myself by disabling the reverse switch would fall into the same category as defeating the deflector chute and sending a rock across the street to hit someone in the head or smash the windshield of a passing car causing the driver to lose control of the vehicle. And yes I have removed the labels off my mattress.
At any rate you did not mention if you considered the x534 but looking at the specs I don't see much difference between it and the x584.
If I were doing it over again I would chose the x5 series over the x3 and would have to look at the x584 which I don't believe was available in 2010. I would also get the bigger deck as I don't have any restrictions in my yard that would require the 48" deck. At the time I thought the 48" deck was more than enough coming from the 38" deck on my 1999 Sabre. The wider deck would give more side cutting capacity to reach under shrubs and such.