I used to always unsnap just to be sure they were clean... but I'm a little anal about that sort of thing and my girls had horrible invasive poo
I think it depends on your bub too if you need the boosters or not... my pair no way would i have been able to get by without them - I used to have to boost EVERY nappy we used - even though it did tend to bulk the nappies up a lot - but then Georgie was my only newborn in cloth...