I use a variety of different brushes and such when I groom Miss Maddie.
I use a double sided pet brush, Hair Pick (for person, I use it for picking out
the hair and poofing the top knot), slicker brush,and an assortment of combs.
For a Poodle the two must have brushes are the slicker brush and a regular pin brush. For me the pin brush works great when blowing the coat out and the slicker is great for the regular brushing a poofing up that topknot, coat, poms etc.
You want a pin brush and a comb. Fluffing is done with the comb, not a slicker brush. A slicker brush is NOT meant to be used like a regular brush, it will be damaging to the coat and if you're not careful, scratch the skin. If you want to get a slicker, get a cocker slicker and don't use it on a show coat. (if you have one)
A pin brush is used on a daily basis for keeping tangles out. The comb is used on a dry coat to fluff. There is a technique to it, I would suggest watching a grooming video on the subject.
The issue about the slicker damaging the coat is not a everyday grooming issue. That comes up with show coats and what the makes the coat break is brushing it dry. You're supposed to use spray on conditioner for dogs on the coat before brushing the coat and ecspecially show coats.
The comb is normally used after you do the main brushing to make sure you didn't miss any knots. When your clipping the coat it's great to have the comb as well but for the everyday general brushing it not necessary like the slicker and pin. Some slicker's are sharper than other's and of course you want to brush your dog gently. If you come accross a knot the slicker will work better than the pin from my experience.
I've used a slicker brush on our Bichon Frise for 15 yrs and now on my Poodles. I have never personally had any issue's and Ive never been to a groomer that doesn't use one on Poodle's or Bichons.