Best tubes for 700x23c?

[Veronica]

I take my road bike with 23s off road, into gravel, dirt, smallish rocks.... There's no need to go to 25s to prevent flats. Now if you want a cushier ride, that's a different story.

I have a 27 on the rear of my other road bike and it's driving me nuts because it's not as stiff as I've become accustomed to. It's the tire I put on when the bike was in the trainer.

For tubes, I really like slime tubes for flat protections.

V.