I have both. In addition to what Snyper said (forget the "quality" part- ain't no such thing with the 770), the recoil lug on the 770 is frightening to me. On mine, at least, it "fits" so loosely into a barrel-dovetail that there is probably 3/32 inch play in fore/aft movement. And it only goes about an eighth inch deep into the plastic stock. That does't seem like enough surface area for .30-06 (or any other caliber) recoil to me. But apparently it is. So far. Trigger sucks too.
The designer of tis thing should be taken out and shot. The marketing team should also be shot. Twice.
I have absolutely no idea why my purchased-used/abused 770 seems to shoot 3 shot, 1.5 MOA factory 150 gr Corelokt groups, with its rust pitted bore - but then, I've only fired 6 rounds so far. Needs more shooting........ and maybe courage....
I'm still of the opinion that it is probably best used for a dog stake. Or a moose/bear defensive point blank, " trash boat gun", which is what mine is destined for if it doesn't fall apart first.