city select, car seat adaptor or bassinet? REPOST

sunflwr2

We have the city select, and for my shower we were given the infant car seat adaptor, we put it together and it doesn't seem all that sturdy, and kind of awkward.
Baby is due September 14th so i'm hoping the weather will still be nice here for a few months before it gets too cold and am planning on using the stroller alot.  Would you suggest keeping with the infant car seat adaptor or getting the bassinet that is made for the city select?
PS- if you use the adaptor, do you put it on the highest "seat setting" closest to the handle bar?  Or the lower one, closer to the basket?