Quoted from mbwalker:
I bought the discontinued Aeon current probe (maybe $20-$30). It ONLY measures current in amps. You can set the voltage for a default value (i.e. 120V) to estimate power (Power = voltage x current). The newer clamp also measures the voltage, which I believe allows you to directly measure watts and apparent power (without being too geeky, this is what happens when current and voltage is out of phase). I wasn't worried about that, so the cheapie version was fine by me.
Hope that answers your question, I can go into more detail if needed. Just holler if needed.
Thanks! I looked into those a long time ago. I see they are now up to Gen 5. I may go ahead and pick one up.