Both use the same Toshiba A19nm MLC Nand and the Barefoot 3 controller. There are a few differences.
Vector 180
- Power failure management support.
- Acronis cloning software.
- Bracket to mount the SSD in a 3.5" bay for cases with no SSD mounting support.
- Rated for 50GB/day of host writes for 5 years under typical client workloads.
- 5 year warranty.
ARC 100
- Rated for 20GB/day of host writes for 3 years under typical client workloads.
- 3 year warranty.
It appears that the Vector 180 is optimized better for workstations and the ARC 100 is more for normal consumer use.
ref.-
http://ocz.com/consumer/arc-100-ssd/specifications
http://ocz.com/consumer/vector-180-ssd/specifications