I've done it both ways and went back to putting them back on for safety!
No doubt there's lots of wind, no heat issues and if using it for work getting in and out of it is an absolute breeze.
But... If you're driving through any kind of a brush area more than once branches came right in and stuck me in the leg!
Not to mention a couple of very close and dangerous calls that had I not seem at the last second and jerked the steering wheel could've actually punctured a very large hole in my leg.
This is at relatively slow speeds and even then it's almost impossible to predict as a lot of the times you actually hit some brush with the front of the vehicle and it pushes it back up against the side and slides along until it hits the open area with no door and springs in onto your leg!
Going fast like over 30 miles hour some real hurt could happen.
If you're in an open area obviously there's nothing to worry about. But if you're driving in the woods I would give it some real thought before I would consider it. The advantages of having no doors is too numerous to list and in fact I see no advantage of having doors so for me to put them back on didn't make me happy.
Not to mention there was this one time that my wife wasn't wearing her seatbelt and I cut the wheel to the left going faster than I should and had I not caught her she would have rolled right out!
For me there's no question, the doors stay on because I value my thighs