I wasn't clear in my last on the effects. The dot pitch of a PC monitor is too fine, and it's different than an arcade/multi-sync, to look like an arcade/multi-sync. I meant if you scale up the res and use effects ON A MULTI-SYNC, the lines will look 95% like real generated scanlines, though a little smoother.
Something I noticed with the avga is that it makes a multi-sync display brighter. It's not just a monitor or mame settings. It's something signal-wise (I think, though I'm waiting for an answer from someone like Peale on this) that makes the monitor behave differently, and you can hear it in a sort of high-pitched sound the monitor produces only when doing true native resolutions.
Anyway, for the 'authenticity' gig, read the wiki.