Power consumption datalogger

Hi,
I need to create a way to monitor 220 single phase power consumption.

I am currently logging this test with two Efergy E2 units (http://www.efergy.us/index.php/usa/products-usa/electricity-monitors/e2v2-wirelesss-monitor.html) and am disatified with the result. This system uses two E2s. each using 2 CT clamps, a transmitter and a receiver/datalogger to measure kWHs used by two PTAC (single room, through the wall, Air Conditioners) units in adjacent rooms and both rooms power delivered through the same power distribution panel.

I was planning to build an Arduino based system and post the results via imp to database but have seen references to an i2c chip based power monitor system.

Has anyone had any experience building such a system? It seems that I can

maybe this one?
https://www.sparkfun.com/products/11005

…and this code:
http://forums.electricimp.com/discussion/comment/4280

I have one of these:

http://www.bluelineinnovations.com

It reads the power meter to determine power usage (an optical sensor counts the frequency that the black line on the rotating disc appears). It has worked great, except every service they have patterned with has gone belly up. Right now I capture the network signal extract the data and post it. It requires my pc to do this, this sucks.

I would like to replace this with an imp solution, but it means I have to monitor myself (since it would require the imp to communicate with my local network devices, which it can’t)…