electricmgmidget.com
MG's look like they tend to get 200 to 220 watt hours per mile, so a bit better then you can get in the Civic, but I don't think it's enough better to make it worth buying an MG over using the civic you already have that is paid for and has issues with the gas drive train.
I agree that the A123 pouches are going to be harder to work with then cells that are in a nice plastic case with studs on top, but the A123 pouch's have awesome specs and are an awesome price and if you are willing to build a compression case for them, they are also different chemistry with a slightly different voltage then other lithium, off the top of my head I don't know what their voltage is but you will need a BMS that matches them too so that is another hurdle.