If you're tempted with the Quinny Zapp (have had one for a few years) they have their plusses - light, fold up pretty small - and compared with either travel systems, or other small pushchairs, they really do fold up pretty small. But the small wheels can be tricky on some surfaces and at times they can be a little unstable. And there's no storage.
The Petite Star seems to have all the advantages of the Zapp but less of the downsides (seems to recline, has storage underneath), although still has the small wheels - and maybe the same stability issues that the Zapp can have.
Although you can mount various car seats on either, I'd perhaps be tempted to have more of substantial pushchair for the first 6 months.
The first "Travel System" I had for our first (probably bought in 2004) was a Britax travel system, had the car seat and everything else included. It was thoroughly dull, but I have to say, probably the best compromise of all I've used. It was light enough (just) to be used every day (I'm thinking more about mums having to shift them about and load them into cars), and fit easily into the boot, the car seat was easy to use, and not too bad to mount onto the pushchair. And it had everything included and never let me down, and performed well in lots of different circumstances. Small-ish wheels, though, so not great for lots of different surfaces.
After that, for our first son, I bought a small flimsy pushchair (about £40 from Argos) that was perfectly servicable - it was small and lightweight, and was really bought to be convenient whilst we were at a wedding (rather than the larger travel system we had at the time), when our first son was about 8 months.
Not long after that, we bought a Quinny Zapp for our first son, and have used it for our second son too. They have their flaws, and are a bit gimmicky and trendy, but they can be very practical, especially when on the move in an urban environment.
For our second son, we bought a more substantial "pram" type thing (think it was from Mammas and Papas) a Ziko Herbie. A lot more robust in terms of the frame, and as a consequence, when folded down, is difficult to fit in some hatchbacks (I'm thinking Golf or Focus sized) because the frame base is pretty large and wide. But as a pram for a newborn, and a pushchair as he's grown, has been good - but more for just walking, really, not that ideal for getting in and out of cars - it's fairly big and fairly heavy, and because of the size of the frame, is more cumbersome when you're in shops or other public places.
I also got a pushchair system (I didn't intend to, but there was some amazing bargain on at Argos, at the time - I only wanted a car seat to go with the new pram - Ziko Herbie thingmy - but for a trivial amount extra, you could have the complete travel system). It's called an Aria and I think is also Mammas and Papas. Not as good as the first travel system I had (the Britax one, for our first son, that I gave away, before we had our second...), but OK as a pushchair, and perhaps more practical than say the Quinny Zapp is.
I guess with them all, it's a case of the old, trite cliche horses for courses - it very much depends on what you're going to use it for and the practicalities. What I would say, is if you're tempted with the Quinny Zapp, have a look at the Petite Star, too. Quinny do a more substantial system, the Buzz, but it always seemed a bit unstable at the front, to me, which is why I bought the Ziko Herbie instead of it.
That is often out of your control <whistles>
