I have the 600W server version of this unit (which btw you don't want to buy if you want PCI-E connectors). I don't have the system put together yet to allow me to really test it, but there are a few things I can comment on.
Although it has 4 15A 12v rails, the combined maximum is 44A. That goes up to 50A for the 700W. There is a 1A minimum load on 12v4 (PCI-E) and 12v3 (drives), but the 44A maximum can be attained through any combination of loads that doesn't exceed the 15A limit on any single 12v rail.
These do not have independant voltage regulation like the OCZ Powerstreams or Fortron's previous generation server units, FSP550-60PLN/PLG, but they are more efficient than either design. On my server unit, the secondary side heatsink is bolted to the case for more cooling. Fan is an Adda 80mm 4000rpm model - the 120mm versions will be quieter for sure.
If you're looking to save money and grab the server version like me, be ready to solder in new wires for the PCI-E connectors - best to not use adaptors to run video cards from 12v3, as not one of the 5 chains of molexes uses anything better than 20 guage wire (ATX and EPS connectors use 16 guage).
Edit - this is the best review of the Aopen 700W (same PSU as the Epsilon 700W) to date, though that's not saying much:
http://www.tomshardware.com/2005/07/...st/page11.html