Long story... sorry.
We bought some TotsBots V2, very happy with them, still going strong about 18 months later.
In Aug 2012 we followed these up with some V3. Very soft due to the minky lining. Lovely for about 9 months and then they started leaking. We isolated the problem and it was that the minky on the inner flap was wicking - water was just running off, which is obviously a bit pointless in the part of a nappy that is supposed to absorb liquid!
After much advice and trial and tribulation we rang Tots Bots. This was either before or only slightly after the 12 month guarantee ran out and they didn't mention the guarantee or any replacement on the phone. They suggested using their own detergent (they were implying that we were negligent by using a different detergent - the only one we could get not to irritate DS's bum) and washing them in washing up liquid, as well as about 65 other things we'd tried (or that are impractical - they also said we shouldn't use nappy cream - i.e. leave DS with nappy rash?).
I just heard a few days ago that the V4 does not have a minky lining and that some customers are getting their leaking V3s replaced with V4. I rang again today and no, they will replace but only within 12 months. Which, as I say, they did not say the first time I rang.
They advertise their nappies as suitable for more than one child. Lasting only 9-12 months is not enough for more than one child.
So basically this is a warning about TotsBots customer service!