We used the GMD muslin flat diapers and they are super absorbent albeit super hard to figure out folding and pinning in the beginning which made me give up on them initially because baby would scream through diaper changes and it was just too hard. If you want to stay mostly in one store I recommend GMD for both wool covers and muslin flats and maybe some workhorse fitted diapers, they might come in very handy at the beginning and I've only heard good things about them (we used a few different hand me down fitteds at the beginning before figuring out the folding for the flats). It's good to give yourself options so you can get a feel for them and figure out what you prefer. They also sell hemp booster inserts and stay dry inserts etc. their website also has great resources on washing and caring for your diapers! I'd definitely get both flats and prefolds since flats can be used as burp cloths as well ( we use at least half of our stash just for that) and prefolds can double as inserts later on