Which payment processor should I use?

Which offsite payment processor works best with CS-Cart for US-based stores? PayPal? Google Checkout? Linkpoint Connect?

We have a few CS-Cart sites which are using Authorize.net, but our server is not PCI compliant, and getting it to the point where it would pass the scans would cost thousands of dollars. So, we are just going to pass customers off to a payment page which is hosted at the payment gateway.

We use Echo.net and PayPal (regular, not pro). 75% of the payment is done by CC and rest is PayPal.