1. Yes. They are quick on target, you can keep both eyes open easier.
2. Depends. 2x or 4x are out there. How long out do you plan to shoot? Best is for you to get out and look though as many as you can. Seem my scout scope review.
For simplicity I'd say keep it fixed.
Pros: Scout scopes do most everything well but don't exceed at anything. They can be taken off for open sights easily if broken. They reduce the risk of "Scope eye" :-)
Cons: I'd say shooting near night time is a negative for these scopes. 25mm just doesn't collect much light. They are weakest under 25 yards. They don't help much with target acquisition and most don't have enough magnification to ID targets beyond 300 yards and the field of view is very narrow. (How many horns on a deer? Who is it?)
A good 2 MOA red dot may be just as accurate out to 300 yards but won't provide any magnification.
Using some good binoculars when in the field for target acquisition and detail helps offset looking though the scope to do the same.