Conclusion: The Z420 is priced fairly for the level of validation and support HP pours into its offering, and this is really where the system makes sense: moderate-demand visual computing for a low- to moderate-range budget.
Pros: Potent performance, SSD plus hard drive storage, Plenty of expansion slots
Cons: No Thunderbolt or eSATA ports, Consumer- rather than industrial-grade hard drive
Conclusion: HP has done a great job of filling this workstation with great components, but still keeping the price low. If you are looking for workstation for your office then I recommend you look at the HP Z line of workstations.
Conclusion: There aren't many reading this that need massive amounts of power for specific and often crucial tasks. But for those who do, and can afford the premium that a workstation demands, the Z420 is an excellent choice.