There was a time when I had 80 shmups for MAME. But out of guilt for unpaid games, I cut it down to the games I own. Thankfully I own many arcade games on licensed compilation packages for my ps2/Dreamcast.
Psyvariar 1 is the only import I own for my ps2 and was hardly worth he swap disks I bought to play it. I planned to import more, but I can afford 100 bucks per import. I can't imagine the guys who shell thousands out for PCB arcade games. Some of the shmup players would sell their first born for CAVE PCBs.