[vec]

There's nothing wrong with typing Vjjjjj until it looks right, and you can still click and drag if that's what seems easiest to you. But if you're thinking of it in lines and characters you're missing the real advantage.

You're still mentally translating a what into a how. You almost certainly don't want to highlight 5 lines down for its own sake, you probably want to highlight, say, the body of a function. Vim provides a command to just do that directly.