Is Pligg any good?
 

Are there other choices? Is Pligg the best? Any known issues with Pligg?

Thanks!

other than the horrible and messy code and not being able to run on large traffic sites, no

Oh yeah that Digg clone...

1. Yes, PHPDug for example, but it comes with the same problems, especially spam.
2. It's popular and flexible, but I personally don't like it.
3. The biggest issue is spam, there are a few very well working auto submitters. These programs scan for Pligg installations and even automatically break the built in captchas.

the spam filtering is horrific, hard to deal with

It's horrible. :)

I started to nofollow links and have seen a reduction in spam but only a reduction. Freain' spammers.

I use pligg on two mainstream sites and spam is not too much of a problem if you're the only submitter. YMMV.

On both sites I combined relevant RSS feeds in Yahoo pipes and then fed em through the RSS feed importer to auto populate the sites with content.

It works for me.