Just watched all 7 and here is my take.
Saw 1: One of my top 2 thrillers (Silence of the Lambs) and one of the grestest movies ever made. Seriously incredible. One of my favorite movie endings of all time. 10/10.
Saw 2: First 75 minutes are boooooooring. All of the characters in the house are one dimensional and Franky G needed to be the first person to die. His Macho bullcrap really ruined it for me. That being said the ending was VERY clever and while not as clever as the ending of the first, it was still legit. The key to a twist ending is that the movie has to distract you from a small detail that the story doesn't want you to realize. While the movie does effectively do that, the first 75 minutes of the movie are incredibly unengaging and the twist ending is not as effective as it should have been. 6/10. The last 15 minutes prevented this from being a 4/10.
Saw 3: From this point on, the series takes a MASSIVE decline. From this point, the series should have taken the route of "Screw the story and put in as many traps as possible" because it tried to be a good thriller and it ABSOLUTELY FAILED. THis movie could have succeded as a trap orgy, but it neglected to do so. The story was far less engaging and you do not give two craps about the main character going through the traps. The acid trap and the rack definitely skeeved me out, so the movie earns a star each for those two traps. I was meh with the rest of them. The characters were more are so incredibly one dimensional (with the exception of Jigsaw) are one-dimensional. If there is any one underdeveloped character in this series its Amanda. None of the twists in the end are thrilling in their own right and made for an unsatisfying ending. 4/10 stars.
Saw 4: Again, should have gone the trap orgy route, because the plot is booooring, the characters are There is too much uninteresting focus on the police goings-on. For an attempt at a thriller, there is nothing interesting going on. The traps were better than the thrid one, but the characters are equally as one-dimensional as Saw 3, except no jigsaw. Also, none of the traps skeeved me out. 2/10 stars.
Saw 5: From here, the series takes a HUGE step up. They actually take the time to explain the backstory for one of the characters in an interesting way, causing the audience to (WHAT A NOVEL CONCEPT) give a crap about one of the characters. In addition to this, the traps had the most interesting dynamic for the traps: work together and you will survive. I really liked this because it was a change-up from the rest of the traps. In addition to this, the movie does the smart thing and avoids what the previous two movies did: It stops trying to be a thriller and just tells you the information as to what is going on. IT lets the traps do their thing and does a good job setting up the sequels. 7/10 and is my second favorite saw sequel.
Saw 6: While the story in the individual movie lacks, the story in the grand scheme of things does a good job of wrapping some details up. So long as the audience understands that this is setting things up, the movie becomes more enjoyable, despite the lack of interest from in in-movie story.. Some of the characters are fleshed out (pun intended) and prevent this movie from being a full-fledged disaster. I really liked the traps in this film, because I did not feel like my intelligence was being insulted (IE the furnace in Saw 2).
Saw: FINALLY! AT LONG LAST! The film series does what it should have done at Saw 3: They said "Screw the story and lets fit as many traps into the film as possible." This movie does not try to maintain its own story and does a good job closing out details from the previous movies in between the orgy of traps. I say orgy because it has more traps than any of the previous saw movies, and it is AWESOME. Sure its brain-numbing, but the traps more than made up for the story. In addition to this, the movie ends on a good note that closes out the series as a whole, while leaving the right questions unanswered. I genuinely did not see the twist coming and it was FANTASTIC. This is easily my favorite saw sequel.
WE ARE THE BORG. RESISTANCE IS FUTILE.