ultra copper IS good stuff, but if used in excess can create problems down the road.
ever see a radiator plugged with this stuff ? to say it ain't pretty is an understatement indeed ! this was used on the core plugs, water pump, water pump housing, thermostat housing, so they "wouldn't leak" [on a small block]. well, it didn't leak.
but the "excess" somehow found it's way into the radiator.........