I have a question about 2CO. How does it implement into Lpanel (assuming its just like Modernbill and other billing programs)? Will it be similar to PayPal? So when the customer decides to checkout they will be redirected to 2CO's website? Or will it be seamless and will the whole transaction take place on my site?

Thank you.

they will be redirected to 2CO page

2CO doesn't support on-page transactions through XML API. For that you're going to need to obtain a real merchant account.