First of all, yes, they will both work. However, there are DEFINITELY a few very lengthy, easy to find threads concerning this.
http://forum.ppcgeeks.com/showthread...highlight=sdhc
http://forum.ppcgeeks.com/showthread...highlight=sdhc
http://forum.ppcgeeks.com/showthread...highlight=sdhc
Just a heads up, there are often more complicated issues where it's easier just to ask rather than search for it, but on something like this, some people will shred on you for not searching for this, and possibly responding on an existing thread.