The obvious question when you're talking about food is "How does it taste?" An MRE basically tastes like any sort of food out of a can does. For example, if you have had Chef Boy-R-Dee spaghetti out of a can, that is about what the MRE version of spaghetti in meat sauce tastes like.
The Thai chicken tastes like chop suey out of a can. It has a lot of chicken, along with mushrooms, celery and red pepper in a sauce that is slightly sweet (in the same way that sweet and sour chicken sauce at a Chinese restaurant tastes sweet, although this sauce is not that strong, nor is it pink). The amount of salt is completely normal for American cuisine -- it is not overpowering, but there is enough to avoid blandness. The rice that comes with the chicken is a mixture of white rice, a little wild rice, peas and carrots and a bit of sauce. It tastes a bit dry if eaten by itself, but mixed with the chicken it is fine.
The crackers are interesting in that they are completely intact when you unwrap them. They look, taste and chew like normal saltine crackers with slightly less salt than a normal saltine.
The cereal bar tastes like any cereal bar -- it is a normal, commercial product.
In other words, if you grew up like a lot of Americans, eating casseroles, Hamburger Helper and lots of prepared foods out of a can or a jar, then an MRE is a completely normal, completely acceptable meal for you. If, on the other hand, you are the sort of person who prefers a salad of mixed greens with essence of cranberries effused in a vinaigrette dressing, along with a filet topped with a caramelized red onion glaze, baby carrots and angel hair pasta on the side, finishing with a strawberry sorbet and mixed fresh berries for dessert, then the MRE menu is unlikely to suit you. Of course, given all that, it is unlikely that you will enjoy any part of the military experience…