Full disclosure, I'm mostly unfamiliar with this franchise. It's been years since I've seen any of these films, and if information from a previous installment is required to enjoy Jigsaw then I went unprepared. I won't be able to compare it to other films in the Saw series and, based on what I just sat through I'm grateful for such ignorance.
I won't keep you in suspense - this film is to be avoided. Jigsaw is a low-risk Halloween season moneymaker for Twisted Pictures, and aspires to be little else. The screenplay is a minefield of detective story cliches and logic oversights. With the exception of a few excellent gore effects, I was bored throughout, and spent most of the film either guffawing at the screen or texting my wife.
Admittedly, I've seen plenty of worse horror sequels, but rarely one so banal. Jigsaw is defined by its unabashed laziness; it's a film that serves up hot spoonfuls of irrelevance without even bothering to set a table. I'm using food metaphors now, that's how annoyed I am. This movie stinks.