MSD Ignition

i have a 95 civic lx w/ the 1.5L engine and i've done some minor mods for my car, i was thinking of getting MSD ignition next. It costs about $300 and I was wondering if it really worth my money or should I save it for sumthin else. How many HP would I gain from this if any? Oh, and which MSD ignition should I get, I heard there was many type (i.e. 6a, digital, etc) Thank for any comment