Yeah, it's the same thing...as long as you followed the instructions on the conditioner package it should be fine...
For a 100% water change, I cup the betta and then dump all the water out. I wash the entire tank, gravel, decorations, etc. with warm water and scrub if anything needs scrubbing. Then add the water & fish back.
I usually just keep my fish in for 50% changes, mostly I just suck out any poo at the bottom and then remove some of the old water and add some treated water.
Varying food is good, I don't think bettas would get consitpated if you just fed them one type of food though...usually that's due to the amount people feed and not soaking their food.
Let's see...I have HBH Betta pellets and Aqueon I believe...and some other pellet idr...I think Tetra. I also have freeze dried brine shrimp that they get as a treat.