I've been using Google checkout for a month. At first, I used it with Cart-manager but sometimes, for some reason, the link provided by cart manager didn't work. Sometimes, buyers simply forgot and I had to resend another invoice, either through Cart Manager or directly from Google. I then quit Cartmanager and just manually send invoice from Google checkout tools. I send an invoice right after buyer makes a purchase. However, I've had 4 buyers so far that didn't pay. I keep resending invoices from Google checkout to ask them to pay in vain. They simply don't pay.
My conclusion is we've got to make buyers pay right after they've made a purchase. By this I mean we need to use a real merchant account which integrates with Ebay
PayNow button so it is convenient for buyers to pay. If they can't pay that way they either forget it or ignore it. A lot of them won't bother opening their email to look for the invoice unless they really want the item. Everybody is busy to do other things.
I do like Google because of its great low fees but am very tired of resending invoice over and over again.
I will go with
Merchant Plus and Authorize.net. That way I can list via Autiva and have the merchant account integrate with Ebay through authorize.net as Apskin has suggested. I know it will cost more but at least it gives me a way to catch customer's money right away.