I bought this after trying a combination of soundboard transducer and fishman rare earth humbucker. it was a great combination that gave me the kind of sound that I wanted, but it also gave me huge amounts of feedback.
The Power Tap promised the same level of soundboard sensitivity but in a system designed for the purpose. it works really well - but I've lost some of the detailed top-end that I was getting from the transducer pickup. Taps sound great.
All in all, I think this is a fantastic pickup for anybody who hits their guitar, but it might be lacking in a tiny bit of nuance for anybody who doesn't need tap noises. For the ultimate, Fishman should wire in a mic with a 3-way blend - or maybe humbucker on one channel with a blend of tap/mic on the other channel.