I did it on my Glee, one year before I sold it. It is not like having expensive slip on exhaust replacement, but I loved the sound of it. It also helped with filtering through stationary traffic as a little blip on the throttle would bring up the roar. Other then that, during the ride you can't hear it.
So, only on crawling and with little blip on the throttle.
On my new Vee2 I have Arrow slip on. Can't even compare it to Glee's exhaust pea shooter cut off.
But, if I had a Glee again and had no money (again) to change the exhaust, I'd cut pea shooter again, no doubt.
Just on the side note, if you decide to cut it off, do it as deep as you can, because the chrome surrounding becomes sound chamber and if you leave a little bit of the pipe sticking out, it will sound less deep. When I first cut it off on my Glee, I did exactly the lenght you can see in the video you've posted. Then I cut some more after few days and got the sound much deeper.