I teach the use of the ARC-1 (and CRP-5 and E-6B) in CAA/JAA ground school here in the colonies, and I even wrote a book on how to learn it at home. You do need to know how to use the wheel.
Advantage - NO BATTERIES - how do you feel about trusting your life to a pair of AA batteries you bought at Wal-Mart, sourced from the lowest bidder in some nasty, undeveloped third world country?
These are not terribly difficult to use, it is just a circular slide rule, and I remind you that we went to the moon in equipment designed on slide rules.
Another big advantage is that if things don't line up, you'll know your answer is wrong. With an electronic E-6B, if you hit a wrong key, you'll be inclined to accept the wrong answer as gospel anyway because "the computer says it is so."
I do absolutely agree that the AFE-1 and CRP-5 are obscenely expensive. The plastic is not terribly durable either. You can buy an aluminum (excuse me, aluminium) E-6B for $25 or $30 and it will last you the rest of your life, you can will it to your grandchildren ("your grandpa actually used to fly manually controlled airplanes way back before using gasoline became illegal"). In the real world,the TAS/CAS/RAS calculations are a waste of time below 20,000 feet and 200 knots anyway - the final correction is smaller than the instrument error limits, so why bother?
Finally, the whiz wheel (of whatever flavor) is the true mark of an aviator. Any w*nk*r can buy a big watch (and many do) and say "Hey, looka me, I'm a PILOT!!" - but proficiency (or the obvious lack of it) with the circular slide rule tells the real truth.
Best Regards,
Echo Mike