I have some but have yet to try them in earnest. As Jim Tyler's findings have shown us time and time again in his experiments, they often result in a more refined firing cycle in most springers, due to lower required release pressure (obviously depending on individual guns' set-ups), so, if your barrel likes them they're going to be excellent. As DJP says, they'll very often be the most efficient too, so maybe giving the option of a little de-tune to improve the cycle even further? And, of course, always worth checking with these more efficient pellets anyway, to ensure we stay within the limit.