You write it's nearly identical to the GB Pockit+ All City. Could you explain how they are actually different? All I find to be different is the max weight that is specified by Cybex (22kg) and GB (17kg).
But are they actually different?
You are right, there are not many differences between the GB Pockit+ All-City and the Cybex Libelle. Apart from the different maximum weight capacity (which is, anyway, very much related to the child's size anyway - you most probably won't fit a 22kg child into a Libelle anyhow), there are design changes. The canopy shape is a bit different - the Cybex's is a bit more in their Eezy line's style (kind of wider), and also, the colorways available are different. I do find GB's fabrics a bit nicer as well. Next, the wheel design and the frame colour are different.
In any case, it, all in all, IS the same design, and the buggies ARE made in the same factory, by the same manufacturer (GB owns Cybex). The functionality will be pretty much the same, so if you're choosing between these two, just go with the one you like more, or the one that is for a better price.