We had the chance to drive the new 2021 Mercedes AMG GLS63, and this is what we thought.

Like a modern-day NFL linebacker, the 2021 Mercedes GLS 63 AMG offers an impressive combination of speed and size. The 603-horsepower twin-turbo V8 engine with EQ boost thrusts the 5,900-lb Benz to high speeds without breaking a sweat; meanwhile, passengers can luxuriate in the GLS63's 3-rows of beautifully blended ritz and tech. It's truly perfect for the family who prefers to have their weekend trips with a side of motoring excellence. That's why I decided to take the $149,740 AMG to the top of Pike's Peak—a place steeped in motorsports lore—to see just how good it really is. 

I embarked from Denver mid-morning, with roughly 80 miles of interstate to the base of the legendary road. On the highway, the big GLS was right at home moving at pace. The seats were extraordinarily supportive and plush, and the dual 12.3-inch infotainment displays worked without a hitch. This particular GLS came equipped with semi-autonomous driving features like adaptive cruise control and steering assist, all of which allowed me to "monitor" the car while relishing in the heated massage-seat function, as well as a thunderous Burmester High-End 3D Surround Sound System.

Before long, those 80 miles were history, and it was time for the real fun to begin. So with the GLS in Sport + mode, its most raucous setting, and the transmission set in "manual" mode, I began the hill climb. Now, I'll be the first to admit that I'm no Michèle Mouton but a few spirited stretches were definitely in order, and the Benz reacted just as I thought it might—superbly. Carving corner after corner, often offering more grip than I had guts, it was easy to forget that I was driving a 5,700-lb 3-row family hauler. The only thing that really gave it away was the GLS's long wheelbase and muted steering feel that made tight hairpins feel just a little smaller and you could feel some of the weight under braking. 

With that said, the GLS could go flat out but its sweet spot is about 60-80% of that. And if that's not good enough for you, you'll just need to abandon your family and buy an AMG GT R. 

Of course, in time, the inevitable occurred. I got trapped behind slow-going mountain traffic and decided to put the beast back in "comfort" mode for a leisurely ride to the clouds. At low speeds, the GLS absorbed the imperfections of the weather-beaten mountain tarmac without drama, and that wonderful AMG V8 burbled ever so slightly just soothing my petrol-loving soul. 

Thus, in unmatched comfort and style, I comfortably made my way to the summit that tested the wits of countless drivers and inspired "America the Beautiful."

In total, I spent roughly 4 hours behind the wheel and felt hardly fatigued. My only complaints with the GLS, if any, is that the transmission in Sport+ could use a more aggressive tune, the rocker panel steps—like other cars—do a great job of getting your lower pant leg dirty, and the ultra-techy user interface likely chagrins older buyers. 

Those are both very forgivable nuances, though. After all, it's a luxurious three-row all-wheel-drive SUV that can do 0-60 in under 4 seconds with the braking and composure to match. And lest I not forget that intoxicating Mercedes AMG V8 soundtrack. Just like that, the brilliance of Mercedes AMG strikes again—just make sure that, if you do in fact get one, you have the name of a good traffic lawyer saved in your contacts.