If at all possible, I'd opt for something that requires less effort and takes advantage of terrain. Digging and covering a proper scout pit is a lot of hard work. Also, concealing the site is going to be difficult because you're going to disturb all the surrounding vegetation. You'll need to get all the dirt someplace else where it won't attract attention (huh? easier said than done). If you look at the last picture on your link the pit isn't camouflaged very well. Supposing you were in hostile terrain and there were hostile (and trained) people looking for you they would probably spot that one pretty easily, even easier with trained dogs.

Another problem is that a pit is, like you said, basically a grave. With generally just one way to get in and out, if any hostiles discover your shelter you won't be able to get away. Observation from inside the pit is going to be difficult at best and you won't know what's going on around you.

All in all, I think a natural cave, properly adapted and camouflaged, would be a much better choice if available. If there are no caves, making a concealed shelter in a group of large rocks might be another option, more so if there is heavy undergrowth. If there is no other way but to dig in you could dig a hole in the slope of a small hill or embankment, then camouflage the entrance. All of those shelters would guarantee better observation and probably better chance of escape should you need to get out fast and unnoticed. YMMV.