Alright, - I've had my hands on many SCSIs and recently SATAs. I LOVE SCSI a LOT. They are VERY nice, the only downside is the price, not the noise, I havn't noticed one bit of difference (I use seagates mostly).
BUT, the drives you are looking at are only 10,000rpm. For 400+ dollars more, the upgrade from SATA to SCSI is not that great. Granted you will have U320 running (good choice), to get the serious performance boost from SCSI you need to grab the 15,000rpm drives.
For this reason, even disregarding the fact that the SCSI option gives you less storage, I would say save the cash and go with the SATA option.
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