Armour Lock is complete protection against all threats, and at greater distances a well timed armour lock can encourage sheild regeneration just as one comes out of armour lock.
While it doesn't give you an escape route if they are close, it will typically buy you some time for someone else to get in on the action, forcing them to break off if they are already injured. Not to mention there is a EMP blast that can be triggered at any time, the only difference it gets larger. So locking, release, and melee could kill a lot of people.
Hardlight shield is useful for the movement, but is much more difficult to use in CQC. Believe there is a emp in it which could be used. The main killers for me is the fact it completely stops sheild regen process while it is active and that it doesn't offer the full protection. It's decent however.
Pretty much all the speed has any relivence to is whether you want to edge behind cover when your sheilds are down. You need team assist if you want to actually back pedal away from a guy, though using it to take explosive/gunfire while your team moves up/away is a cool application.