SDHC or SDXC for Sony CX550v

Hi,

First real post here. Does anyone know which cards are taken by this videocam, or any experience with it using them. Is it important to have the fastest card for HD video? , and what size suits best.

Many thanks

From the specs page: Media Type : 64GB Non-Removeable Flash Memory; Memory Stick PRO Duo™ MARK2 Media and SD/SDHC/SDXC (Class 4) media (Sold Separately)

http://store.sony.com/p/HDR-CX550V/en/p/HDRCX550V#specifications

Thanks for response. So both SDHC and SDXC There are so many SD cards out there. Does a faster card help and if so which?