Ready insulated but heavy usually for what they are.... base unit will usually have been run into the ground before being sold on...
beware ex meat/fish units... you'll NEVER get rid of the smell.
The swivel passenger seat in my 03 (mk6) is a drivers seat fitted to a swivel plinth so matches perfectly (though sits slightly higher duets swivel mech) and has a armrest on the wrong side....
I can get pictures later if it's any help.