I see that nobody has replied yet.
I've not used the UAD personally, mainly because i've gone the iLok route, and i couldn't really justify having another "thing" dangling off the side of my laptop.
If you're going for UAD though, i'd suggest waiting for just a little while, as they just released a new version called the UAD2 Solo Laptop. It's a much more compact version that uses the new UAD2 processor. Since you're using the Macbook Pro this would probably be a better option.
Since it just came out it might be a little while before it becomes available, but i'd say that would be a better buy.