Most ISPs ask for a credit card number so they can bill you automatically every month. It's best to talk to users who have the same skill level and needs that you do. For example, if you're an advanced user who's planning on setting up a website, talk to other users about their experience with their ISP's web-hosting service. Added services aren't any good if you can't get to them because the software is difficult to install. Users who've had problems can also tell you about a service's technical support.
Ease of use is usually the most important benefit of online services.
However, you also need to talk to users of several different systems to see if added services, such as searching, chatting, and shopping were helpful. Balance your desire for particular features against all other available options.