Of the three Resistance games on PS3, which do you consider to be the best, and why?

The third one.

The campaign felt like an ode to HL2. Great game play, great pacing, great set pieces, even great cut scenes.

I agree, Resistance 2's 8 player co-op pve was very addictive. I leveled all classes up quite far, a lot of fun with the randomized objectives.

But ultimately I enjoy single player more, so sticking with 3 :)

Resistance 3 is my favorite FPS ever. The Ratchet and Clank style weapon upgrading and the emotional story combined with just really great scenarios and the bringing back of health packs and weapon wheels just when those were most out of style was simply the best

R3 > R2 > R1

For the reasons others have mentioned.
Really missing this franchise, it was great and im not even a fan of FPS games.

For me, it's Resistance 3.

It has the most balanced, varied, and memorable campaign with the best setpieces, a more relatable player character, the return of the weapon wheel was a bit upgrade over 2, and the way you gain new weapon abilities by using them was awesome.

Resistance 3 was the best for its memorable SP.

The set pieces, grim level design, impactful story, weapon wheel, suspenseful action and New York covered in snow.

Everything about the game felt like a step up from the previous 2 and i loved all 3 games so much and wish for a 4th one to be announced so bad lol

I'm going to say Resistance 1.

The saving grace of the PS3's launch. A lengthy 30 mission campaign, with splitscreen co-op support. It felt like PlayStation could have a new great character with Nathan Hale. The 1940s UK setting was unique. It had the best balance of open warfare and horror shooter elements.

20 vs 20 multiplayer day one on a console was a big deal for the infant PlayStation Network.

I enjoyed 2 and 3 but I feel like they departed too much aesthetically from the solid foundation set by Resistance 1. I feel like that is why the series went downhill sales wise.

A tie Resistance 2 because of the great online co-op and better protagonist but shitty story ending v Resistance 3 better SP but shitty protagonist.

As with most here, R3 is definitely the best game in the series. I am not a MP gamer so on the basis of the SP, R3 trumps the others, followed by R1 and then R2.