Ok, my lpt port seems to be able to switch the radio shack 5V solid state relay ok. Maybe long term use won't burn the lpt port up. I can set it up where the lpt is only powering the solenoids while mame, zinc, neorage, or pinmame is active. My cabinet is idle much more than it's active playing an arcade game, so I figure that is less stress on the lpt port.
Now a question, the solenoid seems to hold just fine with 18 volts, and even as low as 15 volts, 12 doesn't move it at all. Will the solenoid last longer if I use 15 volts, or should I use 18 or 24?