Shall I use Userlist or Mailchimp or Both

Hi Guys,

I'm looking for your valuable feedback here. I'm going to launch my website and blog to build my beta user list. I will have only 2 objectives, to build an email list for earlier beta users and get more subscribers for the blog and other content resources.

Shall I use MailChimp for both audiences

or

Shall I use Userlist (for beta access user) and Mailchimp (content subscribers)

Cheers!