I never used to be a fan of lightgun games until recently, and now I really want to have Time Crisis working in my cab. It only runs at 60% on the computer I just picked up in MAME.
I know that this isn't really an answer to your question. But, if you've caught the lightgun game bug, and your cab has a CRT in it, you won't be able to do better than a Playstation2 set up for RGB (or whatever the best input your CRT can handle), a Guncon and a Guncon2. There are many very good arcade shooting games (over a dozen) which can be played on this setup, and no emulation / hardware woes. I have a setup dedicated to shooting games, and have just about completed my collection of all of the games which support it (damn you, rare and expensive Elemental Gearbolt). Trust me, after screwing around with
all of the other options out there, this is the only one which delivers the real arcade experience. If you are running RGB, you can use a switcher to go between sources to make things convenient.