Car seat and/or car seat + stroller combo

Does anyone have suggestions for a car seat? I just started setting up baby's room and figured car seat should be top of the list so be able to bring baby home from hospital. A friend suggested the Chicco key fit 30. Wanted to ask here before I surf online for suggestions in case any of you ladies have already done your research. Also what is your reco. on buying car seat standalone vs one that apparently also turns into the seat for the stroller? Thank you so much for the help - much appreciated. If you could suggest specific models would be helpful as well.