Hey, and welcome. I'm still an FNG myself. I'm a stay at home father of twins, who also has a full time job, so my schedule is nuts. Shaving my head in peace is a luxury I am rarely afforded. I started by having a barber do It for me. After the one time the barber did it I knew it'd be for me.
I got the headblade right away and I love it. Back when I first started I was shaving almost every day (after I worked my way up to that). Now I honestly shave whenever I feel like it. If one week is crazy then I go a week without shaving.
With that said, I think it's all relative. If I have let the hair build up, shaving may add significant time to my shower. But when I shave daily it's extremely quick. So either a little extra time every day, or a significant amount of time once in awhile.
But I also have a beard, so shaving in the shower also requires me to shave some outside the shower in front of a mirror.
Regardless, you'll find what works for you. I never shaved my noodle with a reg blade, so the transition to the headblade was easy for me