...says marketing! Engineering says there is no such thing as zero-loss, unless they are made from superconductor material.

That's not to say the aren't any good, of course. All of those modern connecters listed above will be better than the older Molex/Tamiya connectors. And yes, you'll need to change your charger, OR simply make an adapter using the old Molex plugs that you cut off your battery pack! (by the way, cut the old connector off one lead at a time! If you cut both you'll probably short the battery using the cutters!)