Xbox 360 memory unit

'Aight, so I bought the 360 memory card so that everytime I went over to my friends house we didn't have to wait 15mins for my profile to recover. However, I now realize there is no way to copy the profile onto the memory card so that it is on both my HD and the card. So is it like, every time I want to go to my pals house I just quickly transfer my profile onto the memory card? 
 
That seems a bit weird 
thanks

just keep your gamertag on your MU so it is easy to take around then you can always plug it back into your system and play your profile from the memory card thats how I have been doin it.