We have the Dr Browns mixing pitcher here. You can only fill the pitcher 1/2 way with liquid and powder and pump it very slowly as it easily leaks out the top of the pitcher all over where you are working. Yes, pumping it slowly will take a lot longer to mix but I felt it's better than a big formula mess all over. It's kind of a trade off, take longer to mix or spend the time saved cleaning the counter. Depends which you prefer. Hey, some people really enjoy cleaning.
Given that you can only fill it part of the way to avoid a big mess, it ends up making about 16-18 oz at once max, not the up to four 8 oz bottles listed in features. Even when I tried to fill it with more, so much spilled out the top that I lost at least 8 oz of formula with the leaking.
Pampered Chef makes 2 larger sized mixing pitchers that don't leak. I'd try those, a blender stick or a blender.