Had the pleasure of watching this in a theater with a small group of Saw franchise fans.
When *those two* characters were revealed, respectively, we all lost our minds.
The patient pacing in the first half of the movie gave the second half tons of deserved emotional impact.
On the topic of pacing, I have a nitpick that the time between the first and second deaths seemed to stretch on too long as new plot element was introduced. Once the story was going at a breakneck speed it should have maintained that momentum. Granted, it did gain momentum back by the end and was very satisfying, but the movie has a CLEAR bathroom break moment if that makes sense.
Anyone new to Saw should consider watching this movie first. A great villain should inspire debates about ethics and morality and John Kramer's awful but weirdly sympathetic philosophy is fascinating in that regard. In a way he's an optimist, believing in change. In many, MANY other ways, he's a total monster. Watching Saw X first will start the pendulum swinging towards a sympathetic Kramer, while watching the original Saw first definitely swings it towards monster. Who are we ever really rooting for in these movies? You don't know, and that's why they're fun.
I almost wish I had the opportunity to delete my memories and rewatch the whole series contextualized from the beginning like this.