BOSS Ve20 Good for a metal vocals?

Im about to buy the BOSS VE20. And i have a couple questions to people that have used it before:

​

1. I read that you cannot use multiple tone/sfx plugins in to 1 preset?

But Combining one of the Tone/Sfx plugins (like distortion) with reverb/delay should work right?

Or for example distortion with doubler/harmonizor?

​

1. I also read about that you need to put the correct key in on evey preset, do you also do this when not using pitch correction?

​

1. And last thing is i know the way of switching through the settings by foot during a live show isnt ideal, however do you get used to it? I want to switch the presets voor verse/chorus fairly quickly.