Those are absolutely fine. I have those
batteries, and I have a different charger, the Trustfire TR-001, that I'd also recommend - I bought it before I ever heard of MadVapes, but I've known other people to get that charger from MadVapes and they love it.
My own personal preference would be for the TR-001 only because it has a more traditional 'plug' that has a cord running to the charger, where the MadVapes one is the kind where the 'plug' unfolds from the back of the charger. My preference is due solely to the fact that the TR-001 plug takes up less 'real estate' around the socket, where the MadVapes one may cover up some of the socket next to the one where it is plugged in.
I do have another charger that is for a single 18650 and it has the plug that unfolds from the back. Since it is only meant to charge a single battery, it can be plugged into a socket so that it doesn't overlap the 'next' socket.