I found them to be very consistent as far as reliable ignition at low temps and when measuring velocities. They seem to be about as hot as CCI BR in the cartridges I have tried them in. 308Win, 6mm Rem, 6.5x55 and 7x57. Good primers for the price.
If you have to ship them you won't save anything on them unless you purchase in quantity.
They work well though as far as I've seen. They do tend to be a bit harder than most commercial offerings.