2) You may stink a bit. (I know not a selling feature) Your body needs to get used to actually sweating and it's trying to push out all the toxins that are built up in your pores. To try and combat this an armpit wash during the day does help. Even pack some baby wipes with you and give your armpits a scrub down midday and reapply.
3) To help get all the "gunk" out of your pores exfoliate your armpits a few times a week. Nothing too rough since it's a sensitive area, but enough of a scrub to get the job done.
4) Drink lots of water. Since you'll be sweating you'll be loosing some hydration.
5) Stick with it! Switching back and forth doesn't give you all the benefits you're looking for by making the switch. The transition period isn't that long and you'll be happy you did it.