Neither.

The inventory into which they put award bookings is simply horrible rooms.

If you want to go to Hawaii, use the SPG355N rate for a paid good room with 5th or 6th night free, 35% off rack rate and double points.

If you must use points, go to the St Regis on Kauai.

I much prefer the Westin Maui to the Sheraton but if it has to be on points choose the Sheraton as their worst rooms are less terrible than the Westin's worst rooms.