I have one that I'm trialing.
I have to say, I really like them and i will probably buy more, but then again i got on very well with mothercare smartnappies (which seem to be very marmite with a lot of mamas) and they are quite like those except the "hammock" that the insert fits in is removable. They're not like Flips in my opinion.
One thing to bear in mind is that my DD is a light wetter during the day. We almost never need to boost (generally use Easyfits and BG V3 or Flips with microfleece inserts) and very rarely have leaks unless something fits poorly.
I'm not sure whether i would want to have a stash of just Gdiapers but i enjoy using the one i have and have my eye on the birdie print one on their website