I have had two Cadac' over the years. A large freestanding one and a smaller table top version (I cannot recall which is called what)
DONT look on either if them as a BBQ, because thats not what they are. If you like the smokey tang of a charcoal (or gas) BBQ dont think thats what you will get from a Cadac, you wont!
The freestanding one has a large cooking area so can be used to prepare a fair biatof food at the same time, But, and there is always a but isn't there? The cooking plates are very large, and are a right pain to try and clean in a campsite kitchen (let alone a caravan sink)
they are just too big to fit into a sink. In addition the entire device does take up a lot of room both when assembled and when packed away. Once assembled it really has to stay outside or in your awning.
The smaller tabletop Cadac is a lot smaller, so is really only suitable for 2 people. The cooking plates are (unsurprisingly) a lot smaller and do fit into a standard sized sink. Being table top it all folds away into a fairly neat storage bag that is a lot easier to store. You woukd struggle to roast a joint of any size in the smaller version, but it is great for breakfast and a few sausages and burgers.
Having had both our preferred option is the smaller table top version. If there was more than 2 of us then the tabletop wouldn't be big enough.
We love using our Cadac, and wouldn't be without it.
Hope that is of some help.
Oh, and if you do get one be sure to add an outside gas point rather than having to keep heaving your cylinder out of the gas locker.