Hello,
If I have to choose between GW-7 and E-09, I will go for GW-7.
Basically, they have same sounds and styles (maybe E-09 has some more sound and style). But GW-7 has analog modify for editing sounds in real time. It also has USB for transfering data with PC (E-09 doesn't have).
GW-7 doesn't come with speaker, its weight is lighter (just 05 kg)
In addition, the appearance of GW-7 is much nicer than that of E-09.
It is my personal ideas (I'm owning GW-7 and I like it) :-D