Yes, you seem to be 10-20% below what should be possible. Here is what I am getting on Ixora:
root@apalis-t30:~# hdparm -t /dev/sda
/dev/sda:
Timing buffered disk reads: 198 MB in 3.02 seconds = 65.55 MB/sec
That with a Kingston mSATA drive:
root@apalis-t30:~# hdparm -I /dev/sda | head
/dev/sda:
ATA device, with non-removable media
Model Number: KINGSTON SMS200S330G
Serial Number: 50026B724A0B583F
Firmware Revision: 541ABBF0
Transport: Serial, ATA8-AST, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6, SATA Rev 3.0
Standards:
Used: unknown (minor revision code 0x0110)
Please note that the T30 will never be able to achieve the same data rates as a modern PC. That said the TK1 has a much more tuned SATA implementation achieving in excess of 130 MB/sec.