Payment gateway with best ZenCart integration

I'm using 2Checkout with ZenCart 1.2.3 and have been getting occasional problems every now and then, due to changes in policy, parameters etc...
What then is the best payment gateway to use with ZenCart? I'm looking to use one with the least problems and needs the least attention.
Thanks!

I would take a look at the recomended products link on the main page.