I used the 3.0 forawhile too and while I did really like them the microfiber inserts started o stink...BAD. And I never had any problems with stink with anything other than those, but from those other diapers started getting it, as soon as I got rid of them it got MUCH better. I personally would recommend Fuzzi Bunz for pockets, they have OS, but I like their sized better, but they run big, to give you an idea...my 20mo is still i nthe smalls and has been since we started using them at about 5mo? so they have really lasted. Or for a one size I would say the BG organic AIO...I LOVE those and they have a version with snaps which is great for babies that like to undo them. But to answer your other questions
How many do you think are needed (if you have the ones that have separate inserts, how many diapers and how many inserts)?
If you go with the BG 3.0 they come with 2 inserts each, you really shouldn't need more than that. Fuzzi Bunz also come with them if you wanted to go with those. Most pockets do but some dont. I would make sure you have atleast 1 for each diaper and then a few extras for double stuffing at night if needed
If you use cloth wipes too, any tips for brands and/or systems? I'm thinking of getting a warmer and pre-wetting them in there so that they're easier to grab. I've heard that the Kissaluv diaper lotion potion is good, but that's about it.
I tried using the warmer and mine got moldy and smelled horrible so I don't recommend that at all. I have mine made by a work at home mom, they are wonderful, but she is on another forum so I don't thik I cn post the link. If it's ok for you to pm me and m give if you can do that. On that same forum (they have a huge WAHM section) there is lady that makes the wipe solution I use too, there are more variety in scents if you do it through a WAHMand it's usually cheaper..plusyour helping another mom out
How many do you need?
wipes? I have like 36..it's a good amount, I wouldn't go with any less than 2doz though, but I use them for lots of things, cleaning up after eating, wiping hands when out or faces, they make great washclothes too. If you meant diapers I would say for a newborn 1-2 doz prefolds would be great for the first couple weeks and then a few dozen diapers (pockets, aio, fitteds) I personally have about 70 diapers and it's way more than I really need lol
What's easier--pre-moistened in a warmer or spray with dry wipes?
I use a spray or foaming solution and just get them wet as I go
What kind of pail and liner did you get to store them in?
I just bought a regular trashcan and then a pail liner from WAHMies