The Powervixxen was the last "NG" thing I got excited about. ACK used up all their goodwill with that one.
I wouldn't consider either of these systems. For a dollar more than the "power" system you could get a 20" iMac which has the software and drivers take full advantage of the system. The "entry" system is way too low power for the price. At least the PV could be excused because it was supposed to be an A1200 add-on.
Both systems (if they even exist) are pointless in two completely opposite ways. One chronically underpowered, the other far too powerful (multi-core, 64bit, PCI-E)for the target OS to utilise.
And it's still odd that despite saying that these systems are complete (sans. monitor) why only the motherboard specs are posted, what about all the other critical components? What size HDD? How much RAM? Very odd, especially considering that summer is close by (entry level system) and these things would have to starting the production process now.