G'Day Tyler mate

Thanks for the review.
I am a big fan of the ATX and, use it all the time.
Will have to look into the S4 Shark.
Based on my past four days of shaving with the ATX and your review, I ordered an S4 Shark. Waiting rather impatiently for it to show up in the mail.
And while I think the ATX is a great evolution for the head shavers, I'm not as sold on using it on my face.
So I gave it a try yesterday morning and...ummm...no. I'd say you CAN shave your face with the ATX, but it shaves your head much better than your face. Keeping the wheels on the surface as I shave up or down across the jaw line was sketchy at best. Along the jaw line? Forgeddaboutit.
Of course, as with all things Headblade, your mileage may vary. For me, trying to hold the ATX in a way that allows for face shaving, caused me some serious cramping in my hand and carpals. That may be the major problem right there.
So I got my S4 Shark yesterday and used it for the first time this morning with the included HB6 cartridge. Love the weight. Love the feel of it in my hand. It's a well-made tool for shaving heads.
I will however be putting the HB4 cartridge in for my future shaves. The HB4 in my ATX shaves very close. The HB6 in the shark didn't work for me. I had to clean up a LOT of my noggin with my Schick Hydro. That in no way takes away from the awesomeness of the Shark. And of course, with all things HB, your mileage may vary.