Instant is just that, instant. You hit the hat to look to the right for example, and the view is instantly looking to the right.
Snap your view quickly moves from front around to the right. Its a minor difference, but with practice you can learn to quickly do a 360 degree scan in less than a second. You "walk" the hat switch around just as fast as the view changes. Just a quick buzz around, if no red cons flash by, chances are your clear and can continue your fight.
Doing so every 3 - 10 seconds builds your SA, gives you a better idea of who's where, who's a threat, and who isn't. You don't need to sit and stare at each view for a second. Just slip around the 360, and if you see a flash of red then go back to that view. Evaluate range, and threat level, and adjust your plans accordingly. The more planes in the area, and the lower you are the more often you need to take that quick look around.
Especially when your in a tail chase, ie your on the bad guys 6, and he's looking to make tracks. Your looking to close the range and get the kill. That is not the time to drop your SA, thats the time to redouble your scans. Adjust lead, fire a burst, scan, adjust lead, fire a burst, scan.
All too easy to get target locked, and thats when someone else picks you off.