I loved the travel system part of my pram (the car seat part) (I currently have a Steelcraft Cruiser) definitely not a wate of money for me - I still use it at 5 months and even tho I have only used the bassinette a dozen times or so - it was soooo handy and saved taking a big port-a-cot. (I have mainly used it for sleeping overnight when we went away/out late to friends.
It is not recommended that you use those bassinets for sleeping for more than 2 hours as they don't have the ventilation required.