Barracuda Networks is at it again: Any Suggestions as to an Alternative

You get their filtering power for free and don't have to deal with the
hardware, if you don't particularly like it.

That's not completely true; the Barracuda appliance uses both block-lists and content-based filtering. The block-list is free for anyone who wants it, but the content-based filtering is not.

However, the block-list *is* now one of the best ones out there. They had a rocky start, but in the last year they have consistently outperformed most of the other no-charge block-lists both in terms of catch rate and false positive rate.

Spamhaus has long been one of my favorites for its performance, but I am now seeing Barracuda beat them each month in catch rate, sometimes by a nice margin. (FP rate for both lists is about the same; VERY close to zero.) If you like Spamhaus, you should try Barracuda block-list and see if it helps in your mail stream. (Every stream is different, so my results may not match your results.)