We have multiple groups of users and want to offer some quizzes to all the groups and some to only specific groups. Are there any basic integration out of the box? Any way to restrict different users from seeing different quizzes?

ARI Quiz has basic integration with Joomla! user management system which means that you can assign a quiz to a group of users.

If you use some third-party component to manage privileges then there should be investigation to see if ARI Quiz needs to be integrated with this component.

We are looking at JACL & JUGA but right now JACL is in the lead. Do you have any group components you recommend or support natively?

Currently the component has been tested only with Joomla! ACL, so integration with third party components will require investigation anyway.

but have any issue come up from you community with JACL (the joomla hack for user/group adminstrations)?

We had a look at JUGA and it looks like that it works in the following way: some request parameters are indicated for a component. These parameters are responsible for allowing or restricting access to the page. In the same way (indicating quiz id) administrator can restrict or allow access to quiz for appropriate user group.

We have nothing to tell you about JACL right now since we have not investigated it.