Best thing to do is try it. Handling HD video requires both suitable software and a decent processor. Having 64bit operating system and video editing sodtware helps.
What processor and OS do you have?
The latest Powerdirector 10 Ultra version is 64 bit software and highly spoken of for HD editing but is £65 and needs a 64 bit operating system to work.
I use Sony Vegas Movie Studio 10 Platinum on a quad core Athlon with Windows 7, 64 bit. This is fine but the Sony software needed a small hack to make it see more than 2GB.