A website does need to look good, but simplicity should be the goal IMHO. A web site should NOT make sound unless explicitly asked to do so. Introductory videos and flash presentations might be nice for those browsing around and needing an introduction to a product, but when I know what I'm looking for, it's just annoying (unless it's very short). Web sites are for information, so take me to the useful data as directly as possible.
The Railguard site seems to strike a good balance, except for the siren. Relevant info is right near the top.
The worst are the sites that have nothing more than a brochure and contact info. Next site please.