I personally use the fleece and the cotton bottom, and I like the results I've had with my girls, and they seemed to love the softness of it. We wash the fleece blanike once a week, and because they are quite trained, I', quite fortunate enough with no peepee leaking through. However before they were trained, I had 2 layers of cotton beneath the fleece, so it was also VERY absorbent. I change their potty pans everyday, so no smell. If they poopoo on the fleece, I just sweep it up with a dollar-store bought broom!
They tend to be quiet during the nights, that is they've had their share of floor time earlier eveing. They seemed to be most hyper at floortime, because that is when I also give them dinner.(7pm) Once they see me spreading out the playpen, they start cooing and stand on hindlegs, as if.... ARE YOU DONE WITH THAT PLAYPEN YET? Once they had their veggies, they start running in laps, then use the haybox, then.... nap on their cozies. They usulaly will become active again around 11pm, then we'll put them back their home around midnight, and refill their pellets for the night.
I use carefresh only in the potty pans, so quite a cost saving and controls ordor very well.
I don't know much about the sac cleaning for boys, and I don't think we are brave enough to undertake such a task, so we opted for girls when adopting. But, I've also heard about boys being more cuddly and curious.