Great choice on the eGo. You won't be disappointed at all. I was going to say in my last post (but I forgot), that yes, you can use cartomizers with the eGo.
Another thing you might want to consider...Totally Wicked has a charger that will charge 5 batteries at once. TW has the "tornado" which is the exact same thing as the "eGo", only with a different name. Their charger is on sale right now for $17.49 (I think that was the sale price). I have one (but didn't get it at the sale price, darn it) and it's great to be able to charge more than one battery at once. You do have to buy adapters to put on the charger, but they are fairly cheap. Since the two of you would be using the same batteries, it seems like it would make more sense to have the one charger instead of several. Just thought I would mention it.
Here's the charger:
http://www.totallywicked-eliquid.com/products/e-cig-accessories-510-titan/e-ni-510-titan5-battery-mega-charger-product.html
Here's a five pack of the adapters:
http://www.totallywicked-eliquid.com/products/tornado-e-ni-accessories/tornado-battery-mains-charger-adaptorx-product.html