If I could give this a, 3.5 I would.
At the time of writing this, I've only seen this film once, (when it was in cinemas) so I'm going to go on the sort of impression that specific viewing gave me. The worst aspects of this film lie in things such as cliches, lazy acting and vague/unresolved plot points. However, this film did do a lot of things right too, unlike the other more recent entries in the saga. It pays far more respect to the original two movies (instead of just using them as a starting point for more mindless robot v robot action scenes), and sets up a new and unique storyline of its own which deviates from the source material - (once again, unlike T3 and TS, which were just rehashes of "terminators attempt to kill John Connor"). The CGI feats are phenomally well done, and Arnie is as good as can be expected. I could go on, but I'll just leave you with the main pros and cons:
Good: Tries to be unique, visibly more effort put into the plot, great fights scenes and CGI, classic callbacks, just the right amount of humour, and of course, the Governator.
Bad: Still quite cheesy despite redeeming traits, plot points muddied with vague time travel jargon, shabby acting on behalf of our TWO MAIN CHARACTERS (Emilia Clarke and Jai Courtney), lack of likeness between the previous and newcoming cast (Yep, looking at you, Emilia and Jai!), sets the ending up for the sequel - which may never be made.