In this detailed article, Timothy Prickett Morgan from IT Jungle compares System i price and performance to Unix boxes from IBM, Hewlett-Packard and Sun Microsystems.

I suggest reading the story if you want all the dirty details, including tables with all the specs. But the bottom line conclusions by Morgan are these:

• System i entry boxes should have the Power6 chip sooner rather than later.
• i5/OS is too expensive.
• DB2 on the System i is too expensive.

Morgan said System i lags on price-performance more because of the software than the hardware.