Pulled this off of their Facebook:
And some more info from the comments:
S-Series mower & it will have the Kohler engine on the 48" & 54" in this series & has LED lights, suspension seats w/ arm rests, & 5" deep hydraulic lift fabricated decks. The E-Series will have B&S engines in 48" & 54" no suspension seat no lights, & the same deck. Alot of the B&S engines are now manurfactured by Dihatsu in Japan & have alot of improvements over the old ones.