There are two major pros to using technology to assess student learning. First, assessing student learning via computer is faster and more efficient than doing it in other ways. Computers can simply score student work as the students take assessments. This means that teachers do not have to take the time to grade the tests themselves. Second, assessing student learning via computer is more objective than doing it in other ways. If human beings grade student assessments, they are likely to have problems being fair. They might grade a particular test badly based on their mood, or the fact that they are hungry, or the fact that the student has bad handwriting. Computers are not subject to such problems and all assessments will be graded objectively.
The main con to doing this is that tests that can be given by computer are inherently limited. These tests have to be multiple choice. Computers cannot, at this point, judge written answers. They cannot judge projects that students submit. They can only grade such things as multiple choice or true/false questions or questions where the answer is a number. This severely limits the sort of subject matter that can be tested and the sorts of skills that can be tested.