Of the two you have highlighted, the first one looks the best deal to me with all the spares you get with it. Neither of the two buggies has a motor or esc included, so you would need to buy these separately. When a buggy is referred to as a 'rolling chassis' it tends to mean the car is complete minus electrics, i.e. ESC, motor and batteries.
As for what else you would need to buy. Well a motor, an ESC, two or three sets of batteries, a charger, a discharger and some pinion gears. You will probably also need some electric connectors such as Deans or Corally type and a soldering iron if you dont already have one. This may sound alot but I think this should be everything needed for a considerable amount of time!
Hope this helps.
