AR is faster depending on your latency. But basically, it's 1.2 seconds max if you're close enough to the target.
If you're far enough, icebolt spamming would be faster than loading up AR and aiming, then risk missing. Besides, if someone's using AR, you could always just charge him and then continue spamming.
r1 AR first shot can be fired right away and hit. The extra aim rate makes it almost instant maxed. If you are charging with wand, chances are that you will only be able to smash with the wand.