I also live in MN (in the cities) and my 3rd grader took the SCAT this fall. Next year we will probably do the Explore. We didn't do at all for the talent search possibilities at all (at least now), but to give him the opportunity to do a timed, standardized, test that really might be difficult for him. It was informative and since we never have given DS a full assessment it continues to fill in the holes for us and helps us realize we are on the right path with him.
The other thing is that it has the potential to cover our testing requirement for homeschooling. I actually don't feel like the SCAT does, even though it might count. But the EXPLORE is more comprehensive and I would feel comfortable going with that as our sole test for the year. We'll probably do further oral testing at the end of the spring for him. Also, if we do return to school at some point it might be useful info to have to help advocate.