I like the P182 but one thing that got me concern was that I hear in one of the reviews that there are issues with the cables of the PSU interfering with the fan down there something like that, you should check newegg reviews so you can know about that "issue" more.
IMO but cases looks good 1 con for the antec 900 is that the drive bays for the HD are not sided but thats just me, 1 con for the P182 is that I don't see much airflow without comparing the case with the 900, lol.
Both cases are good choices is a matter of your "taste".
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