I'm sort of favoring Max by Decision -- I think Kattar's boxing and physicality will allow him to land some very hard shots, particularly early on -- he might even take one or both rounds, but I think Max will start to take over in the second half of the fight as his cardio and five-round experience starts to shine. Calvin has experienced less success against lengthier kickboxers who can tag him at range (like Moicano and Zabit). Max's reach is actually less than that of Calvin despite their height being the same, but Holloway is pretty good at artificially inflating his reach by fighting long and keeping his punches straight and firing them straight down the pipe. I suspect he'll mix in some leg and body kicks here as well, as Volk did against him in their first fight.
I've seen some suggest that Calvin might be able to beat Max the same way Dustin could -- by being able to match him in regards to boxing fundamentals while being the bigger man in the cage, more powerful, with longer reach, etc. However, Dustin had the cardio and experience to consistently hang with Holloway for 5 rounds and pressure him for the duration. Even then, Poirier took plenty of shots and lost one (arguably two) round(s) depending on who you ask.
I wouldn't be overly surprised to see Cattar get the upset. In all honesty I hope he does -- he's one of the more exciting and game guys at 145. I like watching him, more so than Blessed in all honesty. But when I run the fight through my head, I see Max getting the nod more times than not.