1.) All drone manufacturers overstate the flight time by about 5 minutes, so this is normal. To get 30 mins, you have to be flying forward at a certain speed in no wind. You should get around the same flight time as the original mavic pro, or a minute or two less than the new one.
2.) The evo's video is very stable even in high wind.
3.) The Evo's range is at least as good or better than the original mavic. I have a mavic and it's signal can break up at one mile in the city.
4.) When flying max speed, you will see the props in your shot but the video should remain relatively stable.