It's actually as fast a method as any, the limiting factor being your disk's read/write speeds.
I don't myself have a macro that does quite what you want and there aren't enough details like folder and filename patterns in your post to write anything specifically for you. But fortunately you'll probably find a good starting point looking at other macros submitted here that move files to a new folder.
Move Selected Finder Items to Choose Folder , for example, might be a good starting point for you.
Or you might look at a few shell scripts that make it pretty easy to move large numbers of files around.