we took an gazebo down to cornwall and ending up having to buy a tent cos it blew down!
cons- not robust enough in exposed areas
can't keep extras(people or equipment) in there as not as secure/waterproof/warm
LOTS OF SITES CHARGE EXTRA - i have seen loads of sites which charge extra for gazebo when an awning is included!
pro's - cheap and generally lightweight
we have a freestanding awing which is quite heavy and bulky to carry with us - if you are just on site for a day or two it seems a lot of work to put up but it probably doesn't take much longer to put up than a
gazebo vs awning - we have also used it as sleeping space and becuase it is fully wetherproof can also set up electric items in there or put clothes to dry etc
bowever it was very costly over £500 new
this year we plan to go to europe and would like to get someting to provide shade - we do not want to put a windout on yet as we plan to trade in in a year so but have fund a produt by suncamp which fastens to the awning rail of caravans and prop up on tent typpoles so may try one of these