You mention a mac pro, then MacBook. I assume its a MacBook pro? Whats the CPU speed, ram etc...?
The general rule is the faster and more ram the computer has the better. In saying that depending on how much you are pushing it the MacBook should be fine... and its portable?
The UA duo is an added bonus as there are great plugins and you are freeing up CPU.
I am using a MacBook pro in my studio (using Logic).... an only occasionally need to freeze up tracks.