We invested a reasonable amount in a Drifta, and after using a few times are very glad we did.
Having bence space, especially with little ones, is a godsend.
Takes just 2 min at the most to erect fully.
Gives you somewhere to leave all the cooking things.
Doesn't utilise a sink as such, just a plastic tub that sits on a shelf with rollers under the tap.
Does take up 30% of the inside trailer capacity.
Easy to remove (for whatever reason). A couple of times I've taken it out of the trailer and put it into the back of the Pajero for various sporting events. Works a treat.