In my experience, the Mooney M20 series are not suitable aircraft for anything but the smoothest of grass fields.
If you look at the geometry of the nose landing gear, you will see that if the nose gear drops in a 10cm hole, the prop will actually come down a lot more than that. The 231 is probably worse than the 201 in this aspect.
My friend with a 231 found this out the hard way, his first prop strike was on a grass field near his home, where his maintenance shop is based, luckily, only paint was damaged on the prop. His second prop strike was in Spain, when taxiing out for departure, on the grass parking area. The nose gear dropped into a hole in the ground, impossible to see because of the grass and bad forward visibility over the nose in a 231, the prop was damaged, engined needed teardown, new three-bladed Hoffman prop was ordered. Total cost over 15000 Euros.
Also the rubber donuts on the landing gear need to be looked after and replaced from time to time, they are the only kind of suspension in the landing gear.