(When I was less than halfway): I rate this a 6, so far, but I'm staggering between a 6,5, or 4. I heard this was [slightly] better than SAO, but I'll still try and finish to put out my rating. I don't know how this is compared to the light novel, because this is less talked about than SAO, but let me see what it is by itself, because I get a lot of references to COD (Call of Duty) in this anime, which makes me want to keep watching. Story, however is starting to get on the shaky side.
Ok so I finished: and it's bad. It was epic, sure, but weird character development takes away a point, from 8/10, and the cross team communication rule break takes away another. And somewhere in there, fit in story execution, which brings it down to 4/10. The main plot is taken place after episode 6. During that time, the whole situation gets dragged out into the other half of the show, which is annoying when that's only what the entire show focuses on for the rest of the episodes and nothing else. I'd say it's only about 0.1 points better than SAO.