There are many luxury 3-row SUVs fighting for “one percenter” bucks. Is the V8-powered Mercedes-Benz GLS 580 the one to beat? It’s luxurious, stylish and… a hybrid. It also attracts a lot of attention when put into Free Assist mode. It’s also stuffed with tech. Tom Voelk checks out this not-too-big (for a 3-row machine) SUV.