I haven't played the E-80, but I have extensively played G70 and E-50 which use the same styles. The styles are simply wonderful. The vocal processing is also great. The E-80 is much heavier than S900, and bigger.
Only thing I didn't like about the styles is that there is no effective Break/fill. You can program a break, but it just stops--nothing plays for a beat.
There are PLENTY of extra styles available also.
The key feel on the G70 is among the best of any arranger on the market. The E-50 is lighter. I'm sure the E80 is similar to G70.
DonM