35. Is it possible to set up groups to text at once? Is it possible to save this group for re use?

Yes you can create groups. Though you cannot reuse groups, however, if a custom list is created as per their condition, on the object, you can send bulk messages to those list of records selected from the List view.

Important Announcement!

URGENT! Please register the 10-digit business phone number (e.g. 555-555-5555) that your organization uses to send texts to consumers in the U.S. Failure to register may cause heavy penalties and disruption to all your text messaging communications.