Do not buy a travel system they are a waste of time and you won't bother with half of it. They are overly heavy and bulky because they are designed to be a jack of all trades master of none.
In all honesty I'd buy a 2nd hand set if you are led around by your mrs that she has to have a travel system. 6-9 months we had ours and then we were looking for a better larger car seat and buggy. It cost £500 and got sold in immaculate condition for £90.
That was all I could get for it and the pram section was used once
You will though ignore all the above and buy a brand new travel system because you will be convinced you need to buy new for little timmy.