Do you like how this works? Where do you store them when not in use?

I just leave mine at home. Bring them when I need them.

Does it really make a difference in speed and performance without these cushions?

Mine are at home too. They are just in the way for how we use our boat.

They looked a bit clumsy to deal with, this confirms it. Thanks.

I have always slept in the filler section on my Active Thunder, until this past weekend, I decided to leave it at home, and slept in the V-berth.

I'll be leaving the filler portions at home from now on. I like having the extra room.