one time (now ex) decathlon employee here although I bought mine long before I was getting any staff discounts!
my opinion on the base seconds : the key is the ease of setting up and storage. there is the issue of taking down but practice makes perfect on that.
also when you get the delta shape, at a shoot in balbardie mine turned into a hang glider and I was literally 6 feet off the ground hanging on. the lack of a ground sheet was never a problem as I had a separate one to keep things out the mud. convenience in iffy weather was big plus
I felt at the time I was working with them that the more recent generation of tents werent as good as the base seconds. They were more fiddly and always took longer to set up for displays and that was indoors or in good weather outdoors. we never set up tents in poor conditions because of faff. taking down was time consuming as well again indoors.