No need to worry, you can use a different account to go with your Google Checkout. We have one just for business.

As far as not recieving any chargebacks in Google Checkout, that is false. We have recieved some chargebacks through Google. They also do review your orders as well and verify if the buyer is fraud. However, orders do get past them as well. We have had some orders that were cancelled by Google that were deemed fraud and were notified to cancel their order in our system as well.

However overall, it has been fine. Just be aware that to be able to have a google checkout logo in Google Ads you must have a direct link to their google checkout for ordering for that product.