I'd go for (import) Saturn, hands down. Not because it is "objectively the best", but because I myself get much more enjoyment from it. I really love some of my Saturn games, whereas I've all too often found myself struggling to appreciate a "classic" Sega game on the DC. Of course, it helps that I really really love shoot-em-ups. But yes, Shenmue 2 is great, as are Jet Set Radio, Bangai-o and Rez, but as far as I'm concerned that's about it really...
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