First up, a blue I230 in a Loki 480 case. Ran it at a nice low Kn to see what would happen. The blue is a very nice propellant -- even with just a Thermalite igniter, the motor is at full ON within 1/30 of a second. It also has trimodal AP, increasing the density of the motor and as such the density Isp. Finally, the metals content is pretty high, so we get nice white smoke with lots of Isp.