The E-80 is getting "long in the tooth" and the key-bed is "not as good as there Fantom G series". (Roland`s words)
The Tyros 2 & 3 uses the FXS key-bed , which equals to great action.
The G70 uses a completely different style key-bed , I believe it is "hammer action" .
The E-80 as well as the T-2 are geared for home use , and the G70 is more of a live / studio arranger.