Version 1.5.2.20 runs much more slowly than version 1.5.1.19
I installed the new SSD version 1.5.2.10 yesterday and was startled by the very long scan time as compared with the just superseded 1.5.2RC1 (=1.5.1.19). On my machine (1.7GHz P4, WinXPSP2 HE, Comodo Firewall 3.0, Comodo Memory Firewall 2.0, AVG Free 7.5.516), with SSD updated to 01/31/2008, the scan took 55 minutes on one trial and 50 on another. This was much longer than the 20 to 30 minute scan range that I have been familiar with in the past.
To check all this, I uninstalled 1.5.2.20 and reinstalled 1.5.1.19. With SSD updated to 01/31/2008, I ran two more scans. The first, with all SSD immunizations removed, took 20 minutes; the second, with "my choice" of immunizations asserted, took 22 minutes.
It looks to me as if something has slipped rather badly in the release of the latest version of SSD. I will remain with the 1.5.2RC1 for now, in hopes that the fault can be located and fixed soon.