Scoring legislative votes and positions can be tricky and the details should always be consulted. Some senators are notorious for going right for the year or two before reelection. Nevertheless, the ACU score is generally considered reliable as a relative measure of conservative voting.
That’s what I thought, but if Rubio is so high, why hasn’t he taken a stand on anything? And since he hasn’t, it leads me to think the ratings aren’t in synch with what I believe.