Are you working mainly in SD? The V4HD lets you capture and play 8- or 10-bit uncompressed SD (NTSC or PAL) in all formats (SDI, component, composite and S-Video). The V4HD serves as a complete I/O solution for any SD workflow.
When you are ready to make the jump to HD, the V4HD allows you to begin work immediately, with no hassles. No swapping PCI cards, no purchasing extra hard drives, no switching to a faster computer. You can begin your HD work right away. In fact, the V4HD allows you to work in both SD and HD simultaneously. For example, you can work with an SD timeline in Final Cut or Premiere, but monitor and deliver your project in HD using the V4HD's hardware-acclerated up-conversion.
Conversely, you can capture and edit in HD, but easily monitor in SD during editing and then deliver in HD when the project is finished. Just connect your HD monitor and HD deck, and you are ready to go.