With your powerful CPU, yes, latency will be very minimal.
To quickly align vocals on grid in FL Studio, just hold ALT and drag. It breaks free from the snap, and you can just align them as needed.
Sometimes you may also need to cut audio, too. So you can do that with ALT + SHIFT + LEFT-CLICK. This way, when you chop audio, you only move the audio that needs to be aligned, while leaving the other audio in place.
It’s also useful to align just one word here and there. Simply chop, align, and you’re good to go!
Is this the question you are asking? Please clarify!