What should be clear when viewing the individual connector is that the plastic tube is inserted only for transportation and must be removed. If you do not notice, should generally better refrain from such conversions fingers.
Very positive I find the clear end of the connector. So it is easy to check if the cables neatly in contact or should be stripped longer or shorter. Ideally, it is so long that it at the end of the half-shell to the "wall" and comes back about 1-2mm beyond the half-shell. This corresponds to a length of about 12mm.
Another positive highlight is the isolation of the tail. Most banana plugs are made of metal and therefore conductive. It is enough then inattention to a short-circuit to manufacture and at worst destroy the amplifier. In these connectors is not easily possible because plastic does not conduct.
The only criticism that I would like to mention: the contact between the plug and cable is not made by a full sleeve but only by a half-shell. Although this is about 1cm long, but the cable wraps just not complete. It would be through a small design change certainly possible, at least be interpreted as a part of the contact sleeve, which would provide more contact surface with a maximum thick cable or a slightly spread the end of thinner cables.
Finally, a quick note to color ring still: this is a thin rubber band, the going is relatively easy and then it is very difficult raise again. In practice this is not so tragic, because the imprint on the connector (towards the screws) has the same color and not so easy going.
