If you have a GW cart already in - the exploit auto-boots to GW mode with Emunand.
If you hold L with the cart in - it will bring up the menu instead where you can choose other options like loade classic mode, format emunand, dump cart, save, diagnostics, and downgrading options.
If no cart is in - it will just boot to the same menu as if you held L.
for everyday use? No use in it mostly unless you want to play a retail cartridge or use one of the menu options.