s10 rotor upgrade

It wouldn't be a bad idea to flush the old fluid out if you haven't, all that junk that can come off the brake lines, calipers, etc.
Are the S10 calipers new? With the wheels on, are any of them difficult to turn? They should have some resistance, enough to where they come to a stop eventually (within a few seconds), but not almost immediately after spinning. If they stop in less that a second, something is sticking.