Lewaney as I understand (FTM here) you want something soft, possibly not underwired, and with a way of accessing the boob for feeding - usually a clip that easily unhooks. They need to be fitted really once your milk comes in properly which won't happen immediately. I've heard Bravissimo are by far the best place for bra fittings full stop (never mind when feeding). I've got a couple of cheap ones in my amazon basket and I think these just pull to the side, I figured they would do for a starter, but I will wait till nearer giving birth until I see how much more my boobs grow.
I am also researching washable pads but haven't got very far with that so far.
Who asked about weight earlier? I've put on about 7kg, but I'm confused as to where! My bump is still very neat and there isn't any extra weight elsewhere, other than my boobs! But I guess blood, placenta and fluid all weigh quite a bit, even if the baby is still pretty small just now.