I prefer a proper caravan but my parents had a Pennine Pullman (similar thing but with canvas top) and I must admit it towed well. It was quite well laid out and had a large awning. Due to no high sides there is no pull when passing lorries and they can be stored in a decent size garage.
Having said that, you can end up folding them down wet which is not ideal. With a proper caravan you can make random layby stops for tea/loo etc so this is a massive advantage.
As Hercules said, if you get a proper caravan,please please read up on weight ratios/sensible loading/speed etc. They are fine as long as you are sensible. I've towed caravans for over twenty years and many years ago the good lord gave me a slap on the M5 motorway for getting too cocky. I no longer underestimate the importance of
speed and correct loading. The 'folders' don't suffer the same issues so I appreciate your concerns.

Hope this helps.
EDIT: As Entwood said above ^^^^^

(especially the spectator bit

)
Regards
Alan