I opened a trial account.
It's not clear that it really works all that seamlessly. Maybe I am inexperienced with shopping carts, but it seems like you have to enter the price and more info into the cartmanager just to send each invoice. And then it calculates shipping according to the weight of the item, or reverts to a default you must enter.
If someone can show me that this "cart" picks up on the figures in the EBAY checkout and then simply transmits the entire contents of the invoice via Googlecheckout payment, then, yes - I am game. But right now it seems like just as much work to create each "cart" invoice as it would be to just send an individual G.checkout invoice to each winner.
I think that maybe the combination of this cartmanager, and something like authorize.net AND Googlecheckout would do the job.
Someone please take this all the way and let me know what exactly is required. | 
