He has been on a big win streak since he left ufc, with some good wins, sub horn, stopped prangly, and of course the wins over misaki,even though its not a big accomplishment but a awesome ko over salmon.
He currently is the sengoku MW champ and just had What is to be thought FOTY against Misaki last fight, if u havent seen it i suggest you go watch it, he said he wants to start fighting in the states again, and whoever SF or Zuffa picks him up he deserves it.
He is a legit top 10 MW, he is 11-1 since leaving ufc, and the only loss he avenged it, so if u want to look at it he is undefeated, he has improved leaps and bounds since his his time in the big shows, his striking all round has improved, better head movement, footwork, and alot more crisp with his strikes, and of course still got his sick jiu jitsu skills.
I know ppl will shrug this guy off cause he lost a couple fights in ufc like 5 years ago, anyone who knows santiago knows his weakness is getting into brawls, rarely ever he does that no more.
I think he can make a big impact at MW in either SF or Zuffa, i can see him beating guys like Jacare, hendo, lawler, palhares, bisping with ease, wandy,even sonnen, now the other guys like anderson belfort will have to wait and see.