If their opinions are strong enough, it can infect the whole group. Generally, I think it improved dynamics because they always had something to try and talk about. In precalculus, the students' default mode is to put SOME function into the graphics calculator and see what it tells you. Not much help. It takes time to get the hang of the software.
Computers are more of a problem.
Some students liked using the technology and knew how to use it or at least was willing to learn. Other students did not want to take the time to learn the technology so creating a problem for the group. This effect was not as strong with graphing calculators, but groups seem to function better when working with computers. When I had the groups use technology, it was for an activity that could only be done with technology. It was simply a tool with which they were already familiar.