Saw 1- The best. PERIOD. Saw 2 was alright, story faults in parts but aight. Saw 3 is the second best of the series, the game was clever and changed the format slightly by giving the main protaganoist choices though at the end when jigsaw reveals chris's daughter is trapped in a room, they never thought to reveal what happened to her as Hoffman shoots him dead in Saw 4. Saw 4, btw, SUCKED, worst EVER. bascally Saw 3's protagionst script without the cleverness of 3. Saw 5 had the most ingenious traps and games in the whole series. Story lacked anything killer but the game was great.
I saw Saw 6
(geddit)
yesterday. More story driven, less gore. I'm undecided on it fully but the traps were disappionting apart from the last 2. PLOT SPOLIER: The twist at the end when the woman and son get revenge on the man who denied their father insurance was good but the decision to keep Hoffman alive felt it was only there to keep the series going till next year