Kind of wish you could be just a little more specific. I think I have an idea when you say more hardcore, but not so sure what he likes besides, I assume, tamer g/g and compilation cumshots. I think most films fall somewhere between those mentioned.
I'd recommend almost anything by Elegant Angel, John Leslie's Crack Her Ass or Voyeur series, and especially some early Stoney Curtis films. I think Vivid's B. Skow films are decidely more hardcore than what Vivid was more known for. Evil Angel's g/g films produced by Belladonna are supposed to be more hardcore I hear.

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