We have a second hand Polaris, good machine but frankly it spends most of its time locked away, quads are the rural thieves target of choice, a decent 4x4 tractor would be a better option.
I have one and love it, tho for attachment jobs a tractor is a must.
Anyway according to the farming forums one farmer parks his Polaris in front of his shed where he keeps his other quads, knowing they wont bother to nick the Polaris. But for me with the sheep and only gentle slopes its the most useful thing but only cos its the 6 wheeled version with the mini tipper tray back, so I can carry feed and water etc. I wouldnt bother with the 4 wheeler (which I also have as a back up).
They are too slow to round up livestock with, but the advantage of being able to use our red diesel and not keep running out of petrol is huge as we are a long way from any petrol stations.
A decent 4x4 tractor is what is ideal, but they aint cheap!! We manage with a 2wd cos we arent too slopey but any proper slope means a 4x4 for sure. If very steep an Alpine tractor for safety!