First time i saw one was at an camping exhibition (windsor) not sure they are on display anywhere (this was after i had bought one but hadn't pitched it, so was exciting actually seeing one!)
We didn't see one before we bought ours. 5m is a good size. In my tent experience, it's certainly not huge and in relation to modern family tents, it's positively modest in size - well, if not modest then sensible! I wouldn't want to take a family of four away in anything smaller unless I could guarantee ther would be no rain.
I know its still a drive, but if you're heading to the coast on the A64 you could detour onto the Stamford Bridge turn off to Buttercrambe which has bell tents at
Best wishes Sam
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