Yes. 
The way Dragon/Chromium is built is superior. Windows has sandboxing-techniques that can be combined to a powerful sandbox:
- Restricted Token (great for XP-users with administrator-account)
- Job Objects (several restrictions can be applied, such as clipboard-access (read/write), process-launch)
- Alternate desktop (disallows sending of window-messages to processes on the user’s desktop)
- Untrusted integrity-level (Vista and later; denies access to any resource at low or higher level)
IceDragon/Firefox does none of that. (Internet Explorer on Vista and later does some of it.) On Vista and later, Restricted Token is applied, as it is for all non-elevated processes, and it is run at medium integrity-level. (All user-files are medium level.)
Unless the architecture is changed into a sandboxed multi-process one, I cannot see how it could possibly be as secure as Dragon.