These are much more responsive, manuever faster (short) and much more comfortable than a TanDelta Extra.
I am the Josh, Bob mentioned. There are 2 versions of the Hockey fin out there. The longer ones and these appear to be the shorter version. The longer one was based on the excellerator and is similar in performance but doesn't need whiskers. It is not as sensitive as the excellerator as the tips are stiffer for better high power thrust, but the excellerator can take better advantage of small ( think ankle ) movement for hovering and fin sculling. Both are awesome for frog kick!
This, as I said appears to the smaller version, which is even more responsive and manueverable still provides all the go you want. These are the travel Kings, as they are tiny and pack a punch.
It is important to remember, there is no magic fin that will suddenly allow to outswim a current, but good design will allow you to effectively transmit the strength you have into propulsion. All ForceFin designs do that well, much better and more comfortable than any other design I have used.