I recommend multi-fx processors over pedals for beginning guitarists as they allow you to try out a wide variety of effects and hear what they can do.

However, many guitarists prefer pedals over multi-fx processors for the simplicity - less options and real knobs to twist and turn - compared with navigating complex menus and hooking up a computer to the processor to edit patches.

It all comes down to which you prefer!

Hope this makes sense!

Mike