Browser testing can be very time consuming. Which is probably why so many sites are not fully tested.

Using a capture service to see how designs really look across browsers and platforms can really speed up development.

Last year I began using Browser Cam and Browser Shots.

Browser Cam is a commercial offering, comparatively fast, covers a huge number of platforms and browsers, but is fairly expensive.

Browser Shots is a free open source offering, though they do offer priority queueing for a small donation. It does not cover as many browsers or platforms. But it features full page captures.

If you are inclined to sign-up for a Browser Cam account, you can save cash by using a site like Fundable to purchase a multi-user account with a group of like-minded developer/designers.

My preference is Browser Cam do to the range of browser/platform combination and relatively faster service.