While I can't help with the top half of your post, I can help with the last half.
It does make it WAY easier to take the tank off to adjust the valves. I just went through this. I've probably had my tank on and off about 8 times in the last 2 weeks.
The oil does not need to be drained out as long as you have a center stand. However, you will still lose about a teaspoon even on the center stand.