I've never owned a park model, but our snowbird location in FL has recently put some park models in the past 2 years and I checked one out. Had a friend that sold his 5th wheel during last winter and then moved into a park model for about 6 weeks.
Park models are usually more stable than a camper. Not that a trailer or 5th wheel is wobbly, but they sometimes can be depending upon the setup underneath.
I think there's more storage in my 5th wheel than most park models I've seen. The park model floorplan is designed for living in rather than traveling with the sort of "stuff" you need to travel/camp with. There may be some storage in park models, but I think it's somewhat limited.
Sometimes kitchen workspace (counters) is limited in an RV compared to a park model.
That's about all I can add with my limited knowledge of park models.
2018 Chevy 2500HD Duramax - 2015 Cedar Creek Silverback 29RE
16K Huskey EZ Roller Hitch - EU2000i Honda Generator