What are your standards for "best"? Best quality packaging for long life? Best calorie-to-weight ratio? Carb/fat/protein ratio? Most calories for the money? Cheapest cost per unit by case? Pallet? Truckload?
The best of something for one person may be the worst choice for someone with different needs.
In my opinion, if I am buying something to be shelf stable, I would go with a government contractor whose packaging is made to meet the standards.
Watch out for the "A Pack" variety, as most of those seem to come on the market from areas where they were shipped for disaster relief, and have probably not been stored by persons familiar with how to properly store them. Without fail, the darn things flood flea markets and yard sales in areas that experience disasters. Spoken from experience.
I also wonder if MREs as we know it, in tan bags, are being phased out. Somewhere on here about a month ago, I posted an observation I made. Long story short, something called "First Strike Rations" have replaced MREs entirely at my workplace (federal law enforcement agency), and may be doing so at least in some Army units. I was at a yard sale held by a senior NCO from the Army Mountain Warfare School and he told me that he has not seen MREs recently, and he was selling tons of the "First Strike" variety. Though since nobody knew what they were, nobody was buying them. He was asking $4 each, and it looked like a good deal with the quantity of food inside each, but he wasn't selling any, even offering the sealed cases (which look almost identical to MRE cases) at about $20 each. The cases don't have 12 meals in them though, it was some weird number, not 10 or 15, I want to say 7 or 9. I did pick up one of the meals since nobody at work has opened one yet...hmm, perhaps I should open it and review it!