Should you rely on Dreamweaver’s Design view for your Final Design output?
The answer to this question is absolutely not! In fact one should not even rely on a single browser for the final design, but I digress.
Dreamweaver has come a long way in CS4 and CS5 to try to get browser like rendering in design view with the “Live View” button. However, it renders to a single browser, I think Goggle chrome. I can tell you from personal experience that using a single browser to test your web pages will cause trouble. I find that the last browser that I check with is Internet Explorer. This is because it is the most popular non-compliant browser in use. The fact that IE 7 and below are not compliant, makes for some very strange rendering when you are coding to HTML standards.
So, after all that rambling, no don’t use the design mode for final output, and no don’t use live view for final output and no don’t use any single browser for final design output.