We had a convo about him before, Martijn, if you recall. I think he can be a top 85-110 player. Can't argue with the challenger results, he consistently makes QF/SF/F at this level. He's nothing special, but he's got enough game to win matches against guys who can't rush him/take the offense away from him.
Well, this year his W/L record (this week excluded) is only 63.16% in Challengers. I think this best reflects his ability. He has been neither dominant nor consistent.
I actually like his game, but his foray into the Top 100 was a combination of two things: a really shitty year prior to that and therefore very few points to defend, and great success in very weak Latin American Challengers, especially those on high altitude. I think he should normally be just outside the Top 100, probably between 110-130.
Edited to add: if he loses today, his W/L goes up to 67%; if he wins it goes to 70%.