Qurb features

Comodo Anti-Spam is THE best anti-spam I have found and it is free! (Believe me, I’ve searched). However, I have an old copy of Qurb (now owned by CA and they charge $30). IMHO, Qurb is as effective and much leaner (takes only 1.2 MB RAM vs. 13MB or so for Comodo Anti-Spam).

Any thoughts on why someone should switch? Can Comodo learn from Qurb (now CA product). Go to qurb.com and it will take you to the new CA site.