The Yamahiko has a wider frequency bandwidth than the FC. Like what i've mentioned before, it has more clarity and definition because of the higher bandwidth. It doesn't sound choked in some cases of the FC.
Balance between bowing and pizz is also better and i don't have to adjust volume between either anymore.
One thing that amaze me is the resonance that the pickup picks up. It responds like what a microphone would in terms of the tail end of each note. I'm not sure what they put inside the pickup tho.
The one last thing that really prove it's value at $350 is the construction.
Top quality japanese machining and they use a connector call the microdot used in test equipment with a frequency bandwidth higher than what our ears hears. It is almost indestructable as well.
The screw thread that is on the Yama is also bigger than usual American size threads, which means you have to make a bigger hole if you install it. Being bigger, i also felt there is an acoustic sound difference. It's not as choked as the usual adjusters.
Frankly, I'm not a big fan of the clips that's on the site itself as they sound bright and twangy. In comparison to the FC, i can get my sound easily with any kind of amp offered to me during gigs.
I think one of the main reasons why not so many dealers stock them is because of the higher price and the lower profit margin that the maker offer. Anyways, they are great pickups used for piano as well and i still carry them to satisfy my customers.