Buttons are a bit different then the ones on Dreamcast. On Dreamcast they were flat, while on PS2 they are more round - more coming up. The one for PS2 is easier to use I think - the buttons are not too sensitive. On Dreamcast you just had to touch them slightly to register, on PS2 the registration level feels just fine - you have to press/hit the button slightly.
I don't think there are other non-Konami controllers that are better and cheaper. But I think you'll be happy with your Konami controller for PS2, since it was improved from its earlier Dreamcast edition

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