Sticking to CodeIgniter practices vs. making things easier for new developers to pick up

[eluser]Michael Wales[/eluser]
I say whatever will help you develop your application and maintain it the best. Like Jolly said in this post:

My take:
function called from view = helper
function/method called from controller = helper, library, or model

A model is for getting/setting data, whether from a database, file, feed, etc - a fairly ignorant entity. A library class has methods that share and work with its variables. I think a library would normally have more functionality than a model - it could even use models. Maybe a library might make more sense in this case - especially for the payment gateway.