To rebuild, or not to rebuild

I've got a Bosch V8 that I need to do head gaskets on. I'm going to have the heads machined, and I'm putting studs in instead of bolts.

So, my question is: How worth it is it to replace the liners if they haven't failed yet?

I'm gonna have the heads off already anyway, I'd be more than halfway to pulling the block. The liners haven't slipped yet, they seem good, but of course, I'll be doing a closer inspection when I'm down there.

If the liners haven't slipped, should I replace them...

To rebuild, or not to rebuild