I think for most people who get or have seen good deal of mexi brick, good schwag is anything that is commercial but not black, super dark green, or over compressed.

You can still get schwag that is green, strong and cheap. I think most people would call 'good schwag' mids.
But that's just me, i smoke most anything that isn't black or overly seedy which spans from stuff from Mexico, to stuff from my own back yard so its not a lack of knowledge that has lead me to this opinion either.