Which method will lead to less returns?... (auto-generated their username/pw or let them choose...)

Hey Warriors, I have an online course that I sell and I am wondering which post-sale method will result in less returns, less lost pw/username tech support questions, and less "Where's my product" support questions?


-- Method 1) Customer buys on Clickbank (get sent to two upsells), After the upsell process, they get sent to a thank you page telling them to check their email for their username/pw.

Their username and pw are automatically generated an emailed to them right away. They then have to check their email to get this (which the thank you page tells them to do), then they have to visit the login page, and use the auto-generated username/pw to login

*note: the username will be the email address they used at checkout). -->

fyi) this is how Digital Access Pass membership script works


-- Method 2) Customer buys on Clickbank (get sent to two upsells), then gets sent to a post-purchase registration page where they enter their username/pw they choose. An email is also sent to the customer with a link to this registration page. They can then go to the login page and use the login name/pw they chose.

fyi) this is how Wishlist Member works


...Has anyone tried both of these methods? Which seems to be better for the customer and result in less returns, less "where's my product, what's my pw, etc" questions? Thanks a lot.