Every stay I had at the Hilton was upgraded to a suite. The rooms are tired and the beds can be uncomfortable, but you will get a room with decent space.
The car park at the Hilton is pretty compact in places. It only takes a larger car to park inconsiderately and you can find access to be blocked. On two previous occasions, we were delayed leaving due to hotel management having to track down guests and ask them to move a vehicle. I wouldn't even attempt parking at the hotel now as we have a larger car, but last time we drove it was in an Audi Q3 and it was very tight in a couple of places.
A Mini Countryman should be fine though. I liked the comment about the DT Lincoln. We got extremely lucky on our last stay there, as one of the only couple of decent spaces was open on arrival. I wouldn't fancy parking under less favourable circumstances!