I use GK for DS when I run out of my other night nappies, and I think they are brilliant! I put the following into the pocket:- microfibre insert, the double bamboo insert that they come with AND also another bamboo booster inbetween the insert.
This does him all night - and its not too bulky, it never feels wet but is certainly bloody heavy when I take it off him of a morning. The inserts are totally saturated, but you wouldn't know it from the outside

The only nappies of mine that feel damp to touch are the fitteds - even with longies over the top.

Hope this helps!!!!