I feel your pain. I don't know whether 'wget'ting the page using the -p option is what you are after? From the wget man pages:
This option causes Wget to download all the files that are necessary to properly display a given HTML page.
This includes such things as inlined images, sounds, and referenced stylesheets.
I figure timing that operation would be the way forward.
I always wonder though when I am asked to perform these type of checks on public facing pages how it can possibly be of any use to time something over a LAN or hi-speed corporate WAN connection when Joe User might be on some low spec ADSL connection, or, god forbid, 56k dialup... Of course, there's a limit rate option with wget too, but I try and avoid telling them that as all of a sudden "1 check" becomes "1 check for 56k, 1 check for 512k ,1 check for 2Mb..." !lol
Any road up, enough ranting... Hope that helps