Bear in mind I love campaign play and only farm under duress
BL1 - 1500 hours using 25 characters (est. - 273 hours since the move to Steamworks, scaled up)
BL2 - 2944 hours using 12 characters and 7 “mules” (I’m taking an Axton through the game currently)
BL: TPS - 1065 hours using 10 characters & 4 “mules”
As for favourite characters, I can’t separate Krieg and a Melee/Plaguebearer Lilith. Brick comes in a close third.
I love all the Borderlands games and wouldn’t like to choose a favourite:
BL1 will always have a place in my heart as the first of the series. The Knoxx DLC was a classic and there are lots of good mods available. It does feel basic compared to its successors but that needn’t be a bad thing.
BL2 is astonishing in the amount of content released. The length of the basic game leaves most recent FPSs standing and the DLC has been exceptional. However, it was a step up in difficulty. I’ve done the whole UVHM/OP thing on more than one occasion. But, unlike BL1, I never felt like the “badass” you’re supposed to be.
BL: TPS brought the badass factor back with 6 very playable characters, probably the best balanced across all the games. Low grav, cryo & lasers were a great addition to the game mechanics. A bit less “talking” would have been good, though.