Like the others have said the SCAR H utilizes a much easier to find round the 7.62x51mm as compared to the 6.8x43mm. I have had the opportunity to handle a SCAR H/MK 17 (the military's designation for it) and it seemed very well built, fairly familiar compared to the M16/M4/AR15, and more mobile than the M14. One of my cousins is an Army Ranger and when he graduated from the Ranger School (or whatever it is called) I got the opportunity to handle his SCAR H/MK 17.
"It's a gun you loaded on Sunday, and shot all week."
"If God didn't create man equal then Sam Colt had made them equal."
"Fast is fine, but accuracy is everything."