It’s unfair to talk only for the price, 20 euros more or less it’s not a big deal. The most important thing is if it has a good gameplay or not. And here we are talking for a new unique game system. It can’t be compared to Descent, or HQ, or anything else because it’s totally different. Very simple rules, which can be expanded to every direction you want, suspense, and a minimal setup (something very important for solo).
For example, when I am playtesting HQ quests, I find it very annoying to pick up and put the furniture. It’s totally different when you have more players around your table, but when you are playing alone it is very annoying. This is not happening with AEF. There are not many components. You draw the event cards, you move the patrols and you are thinking your next move by drinking your bear.
It could have more boards for more missions, this is the only bad thing I could find. But if you ask me, I am more interesting for new bosses, or new custom heroes with new skills than a different board. The real gameplay is on the encounters and not the exploration.