When I was doing my Navs , I had a plane booked for a 4 hour Nav and the weather meant we could not go. As I had the plane and instructor booked, I decided to gain some experience doing a bit of local stuff. My instructor asked if I would like to do a bit under the hood. It was 20 minutes of the most intense concentration I can ever remember. At the end of it I felt like I had been 15 rounds with Mohammad Ali.
I would love to do some more, it was exhilarating after the event.
It taught me two things for certain.
One is I never want to go into cloud.
Two is that if I find myself in there even with the correct instruments, without a lot more training I do not have very much time to get myself out. I would say 10 minutes at best and that is if I can fight off the panic that would probably be associated with it.