Just curious. I would imagine the session would be finished quicker if using a twinny.
Is there any advantages...in contrast to disadvantages?
Cheers in advance
Sessions wouldn't necessarily finish quicker unless you do a lot of boosting... Twintips don't go downwind as good as surfboards so downwinders would be longer on a twintip if you mow the lawn. Im sure many people do twintip downwinders. They are great for doing big boosts and not worrying about getting back upwind.
Yup I do, all personal opinion I guess. I just prefer a TT over a surfboard. I also have an advantage of working upwind from my home so I will start a normal session then might get the idea to kite home.
Now, one advantage is its easier to hitch a ride from someone with a small car if you have a twinny, found this out when I was on the Sunshine Coast recently. 
There are so many different board options in kitesurfing so I'm not sure why anyone would just want to stick to one board type. I personally like my ocean rodeo mako (twin tip) in downwinders but also occasionally use my standard 6'4" surfboard or a skim board.
Boots are not great when you make an error of judgement a subsequently get rolled by a wave.
