A good friend of mine owns this First 53.5
. It's the racing rig version with deep keel, lazy jack's, 4 electric winches, generator, bow thruster, etc etc, and having sailed with him many times just the 2 of us, IMHO it's too complicated a boat for a couple to cruise in comfort. We race with a crew of 12, and on occasion wished we had more people on board.
It does sail beautifully and can be sailed short handed, but you have to know what you're doing, simple things like mooring are a bitch with only 2 people and no help from the dock.
Secondly, although the deck space corresponds to 53", due to the bow quarters with deck side access, below deck it's more like say a 45", so why pay for 53"?
The other thing is that, although I don't have exact figures, according to my mate, the running costs are horrendous.
If you're considering purchase, I would definitely recommend an extended sea trial, to see if you feel comfortable with handling the yacht.
Don't know the prices down under, but a Bavaria 46 (for example) will give you the same space below for in theory quite a bit less cash, and quality & sailing characteristics are more or less on a par.