Finally purchased the Quinny Buzz, its on sale at the Ocean Terminal, $1000 off the original price. All the others are on sale as well - so worth going to have a look if you want to buy a Quinny. I did loads of research and here's what I found:
Buzz: 3 foreward facing positions and 2 positions when the seat is facing you. I thought since we will be using it for when bub is up to 4 years old, although it is slightly more expensive than the others, its worth the $. Also, it has this amazing unfolding system, you only need to tap it and it opens by itself. But it is slightly difficult to close, in that you need a little force. Better than the bugaboo as you can fold with the seat on, I believe for the bugaboo, you need to dismantle the pushchair before collapsing it.
Zapp: downside is that it only has one upright position. But, apparently it is the smallest ever push-chair once folded ! And very light. A couple of mums I asked really likes it.
Speedie: similar to the buzz, but only faces forward, can also recline the seat but using a harness system. Bit more difficult to open than the buzz. but none the less a good choice.