I'm very happy with my X585 (similar equivilant to the X728) with the 47" blower and 54" blade. It works well with small snowfalls to blade quickly then blow the 2' rows away. It takes 2 minutes to switch from the blade to blower--pull 2 pins, drop the blade, disconnect 2 hoses, drive up/hook up to the blower, attach 2 hoses, attach the short driveshaft.
I'm not sure I'd want to not have 4x4 on the X series if I was blowing snow. True the weights on the back will help, but when it's a bit icy...not too sure how well that would work. Then again, I've always had the 4x4 so I could be wrong about not having it.
Having a dedicated mower/blower works well. I use the 2720/FEL for some clearing/piling where the blade/blower can't go and leaving the FEL on no doubt speeds the process up.
Last comment is the mower off/quick attach/blower on. Very easy and a 5 minute job max--probably a lot quicker if done more than twice per year! You can't have the mower on while using the blower, the driveshaft for the blower hits the mower.