I am such a huge fan of Subway's 5 Dollar Foot Long subs. It is a realy good deal for a sub that is, well, ok. I'm in NJ, the home of some of the greatest sub shops in the world, so a chain sub just isn't going to ever be considered really good. But, here's where the sub excels. It is a measured portion, and will fill one up for 5 bucks with food that is ok quality. Calorie wise, the turkey foot long, my favorite, comes in at about 650 calories. It has fiber from the whole grain bread I get it on, and the vegetables it comes loaded with such as lettuce, cucumbers, pickles, tomato, onions, and peppers. A large sandwich from MickeyD's or the King comes in at around 800 calories, and is loaded with fat.
The biggest difference is I can eat a large andwich from the burger places, and won't be satisfied. The sub can be two meals for me, or it is enough to share with the Mrs.
As far as taste, the Subway sandwich is ok. I like that it uses fresh ingredients, and a wide assortment of vegetables. Five bucks is a very fair price for a very decent sandwich.
They do offer many different choices for the special price, but I go with the turkey because it is the least processed.
On a 1-10 scale, I'd give the Subway sandwich a very solid 8 for value and quality.