These discussions regarding 1 series vs X7xx are frequent.
The common theme in them is people reinforcing their own purchasing decisions with the rationale being, "It must be better because I bought it". Often the author has no direct comparison due to not having owned both but that doesn't stop one from having opinions.
I have had a JD 2305, predecessor to the 1 series for 16 years and a X758 for 3 years.
My observations are:
1. Both are equally stable on hills and I have very steep hills.
2. It is delusional to think any 2 wheel drive is even close to being as capable as a 4WD. The JD 2305 is very capable with the snow blower, turf tires and no weights except the rim rear wheels as long as it is in 4WD. After I get down doing the driveway I often put back in 2WD to park and it will not back up a slight incline on pavement and it necessitates 4WD to put away.
3. The maneuverability of the JD2305 is not much different with the exception of the roll bar hitting tree branches as it doesn't fold.
4. The JD 2305 has a 2 speed transmission and pulls a heavily loaded 6x10' trailer on the hills easily, the X758 having only one speed and geared higher struggles.
5. The X758 mows much better. The JD 2305 with independent lift cannot be adjusted to mower higher than 2.75".
6. Many put loaders on the 1 series, personally I don't think it is a big enough machine.
7. I have 3 pt. attachments that when loaded would be pushing the capacity of the X758. (55 gallon sprayer and spreader).