There are many kinds of spear heads, with lots of different barb configurations. The type with retaining cups and rubber expanders under them are not going to be very fast nor have the best holding capability. They are best suited for when easy fish removal is necessary. IMO locking the barbs down for the shot will often cause them not to deploy. I'd use a single Hawaiian flopper (with no retainer) where speed is desired, or a slip tip (that toggles) for a better purchase on big fish.
Chad
Chad