В общем сабж.
При загрузке через FlashGot 0.5.96.060823 тормозов не возникает, а вот встроенным загрузчиком

Создано: Fri Aug 25 2006 16:02:10 GMT+0400
User Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; ru; rv:1.8.0.6) Gecko/20060728 Firefox/1.5.0.6
ID сборки: 2006072814

Используемые расширения: [36]
- Disable Targets For Downloads 1.0.1
- Extended Link Properties 1.2.3
- Extended Statusbar 1.2.4
- FireFTP 0.94.2 - FTP Client for Mozilla Firefox.
- FlashGot 0.5.96.060823
- Forecastfox 0.9.3
- Forum.mozilla.ru 1.7.6
- GismeteoBar 1.03
- Gmail Notifier 0.5.6.3
- Gmail Skins 0.9.6
- Google Notebook 1.0.0.5
- GooglePreview 1.3.3
- Human URL 0.1.1
- IE View 1.2.9
- Image Zoom 0.2.6
- ImgLikeOpera 0.6.12
- McAfee SiteAdvisor 23.0
- MinimizeToTray 0.0.1.2006030906+
- Mouse Gestures 1.5.1
- Mozilla Calendar 0.3a1+
- Mozilla SpellCheck Libraries 1.0.1.0
- MR Tech Local Install 5.2
- Plain Text to Link 1.5.20060124
- Popup ALT Attribute 1.3.2005092701
- Resize Search Box 0.0.7
- Right Encoding 0.2.1.2
- Ru-Board Navigation 1.4.1
- Search Engine Ordering 0.9.6
- Search Engine Wizard 0.2.2.2
- SpellBound Development 0.9.8.20060108
- Tab Mix Plus 0.3.0.5
- TranslateBar 0.2.3
- User Agent Switcher 0.6.8
- Wizz RSS News Reader 2.1.5
- wmlbrowser 0.7.7
- xSMS 0.0.5.16

Выключенные расширения: [1]
- http://www.google.com/search?q=Firefox%20

Суммарное число расширений: 37

Установленные темы: [2]
- Firefox (default)
- iFox Smooth 2.3 - ifox based on Safire by Bazon Bloch

Установленные плагины: (10)
- Adobe Acrobat
- Adobe Acrobat Plug-In Version 7.00 for Netscape
- Java(TM) 2 Platform Standard Edition 5.0 Update 6
- Java Plug-in 1.5.0_06 for Netscape Navigator (DLL Helper)
- MetaStream 3 Plugin
- MetaStream 3 Plugin r4
- Microsoft® DRM
- DRM Store Netscape Plugin
- Mozilla Default Plug-in
- Default Plug-in
- QuickTime Plug-in 7.1
- The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the <A HREF=http://www.apple.com/quicktime/>QuickTime</A> Web site.
- RealPlayer Version Plugin
- 6.0.12.1212
- RealPlayer(tm) G2 LiveConnect-Enabled Plug-In (32-bit)
- RealPlayer(tm) LiveConnect-Enabled Plug-In
- Shockwave Flash
- Shockwave Flash 9.0  r16
- Windows Media Player Plug-in Dynamic Link Library
- Npdsplay dll