Looks as if your transfer rates are capped at 16mb/s. That signifies your drives are configured to and are running at ATA33. Go fix the problem in your BIOS. Your max sustanind transfer rate should be around 39.9mb/s for a RAID 0 setup, or 37mb/s for stand alone drive. Don't confuse access and seek times. Seek for RAID setup should be slightly slower at 9.5ms compared to regular 8.5ms seek of stand alone drive. I doubt you notice any difference, so don't complain about 9.5ms. Access overhead is another 4.2 ms, so totalling time to initiation of transfer should be around 13.7ms for RAID, or 12.7ms for stand alone drive.
Let me just make sure you guys have your RAID 0 setups done correctly. I will just give you a quick run down for setting up the 75GXP's on an Abit KT7RAID for RAID 0:
1. Each drive is on its own ATA-100 IDE channel using ATA66 cable. So drive one on IDE 3, drive two on IDE 4.
2. HTP370 setup utility -> set cluster size to "16k"; set drive interface to "UDMA5"
3. Fdisk and format drives.
4. Done. Very simple.
Good luck.