Kate goto the cloth thread they are a great help & so friendly.
Personally I love my Itti's they are so trim Maddi can wear all her pants with them. You will find most all in ones are more bulky than, snap ins & pockets.
Really it's just trial and error with the nappies, you'll find some nappies just don't work for you & what may work for L may not work so great with the next bub.
I'd start off with so big name brands like Itti Bitti's, Bum G's, Green-Kids etc only because they have good resale value if you don't like them. As for sizes don't base it only on weight base it more on measurements, Maddi is just over 11kgs & still fits mediums with a fair bit of room to grow but if you do buy some Itti's Bitti's i recommend going large as they a very trim nappy.
Haven't used prefolds, so I'm no help there.

Hope all the pregnant mums are feeling well.

Kaz i'm glad your finally getting some answers

As you can see I'm still here, been getting more pre-labor couldn't get to sleep till 2am last night because i just couldn't get comfy.
By the time she decides to come I'm going to so drained from all the pre-labor it's been 2 weeks now & it's just not letting up!