650 watts is more than fine for that card. It's minimum suggested Power Supply is 500w.
The CS SERIES is a semi-modular PSU, meaning that only the main cables are hardwired into the system. You can pick and choose what other cables are hooked up. Very handy when it comes to cable-management. It also has more PCIe connectors, & flat, low-profile cables. It's also Gold efficiency rated if that means a lot to you.
The VS series is more value oriented. Non-modular (meaning they are all hardwired in and cannot be removed) have less connectors and are standard looking wires with a black mesh sleeve over them.
Either will work. Just depends on if the CS series features are worth the extra cost to you.