Like I said, I bought all of them. Now they are NOT stellar top of the line modules, but the maps are good, the story hooks are good, and even funny sometimes, but they are 3.0 if that bothers you. If you get them because you like how, I don't know a good way to explain it, rough I guess, like the early OD&D and 1E modules are/were, then I am sur you will enjoy these, especially at the price.
If they are no longer on sale I have two suggestions for you. One: E-mail the Trolls and beg them to give you the sale prices on the others.
Or two: Wait and keep an eye out for the next time they put those modules on sale. They do it pretty often. At least it has seemed like it to me since I bought them a couple of years ago. Actually, I think they are almost always that price, if not always. It is the other books that were really on sale, I think.
I'm pretty sure the e-mail will work if they are not still "on sale" tomorrow.