They're not so wildly expensive. a couple hundred bucks maybe. My mom got one years ago, and it's really convenient for quick pour-over coffee. Great if you're in a hurry. I use a moka pot at home, but the 10 minutes it takes to boil while I putter around the kitchen trying to remember my name are really the most worthless of the day.
Minor nitpick here, but it's a fact I found interesting when I heard about it. The water inside a Moka doesn't boil, you can indeed observe that the water coming out from the top isn't boiling. What happens is that the air that is left inside the bottom chamber expands due to the heat, pushing the water upwards.
