transparency in mental ray. please help

[daydream]

hi. for a while i've been trying to figure out how to get fast transparency in mental ray for max. i recently discovered that there is a transparency shader which i tried but in some situations can be muuuuuuuucccchhhh slower than simply alpha mappin a standard material. i've been dying to make like an open field of flowers with alpha mapped flowers and have only found extremely high rendering times with gi. without gi the render times are quite decent. but i'm the kind of guy who can seldomely live without gi. i thought mental ray was good about plain old transparency. i thought it was lightyears faster than refraction. like something with transparancy should literally blaze by. but that's not what i'm finding. is there a way to do this?

please please please help.

thanks in advance,

daydream :D

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