I've upgraded for a cost of £25.09 (39.00 USD)
Was a no brainer for me, but I'm biased because I already use Ultra Analog 1.1 and I like that. In fact I like all of their stuff.
Main plus point for me is the GUI is more like the Chromophone GUI and is easier to operate, for me anyway.
As for the sounds, nothing to write home about... I just like to have a load of options