[robomartin]

OK, maybe someone can explain. Have I been doing it wrong?

I have minimal Windows VMs built on VMWare to test with everything from ie6 to ie9 and a Windows 8 VM to test ie10. Same for Windows Safari and Firefox. With VMWare's workstation software you, effectively, get one browser per tab (well, one vm per tab) and testing is dead simple.

This wasn't so hard to setup at all. I can even remote-desktop into the machine hosting the VM's and test from another machine. The only cost were the Windows licenses, but we use Windows already, so that wasn't too bad.

Why would one want to pay to use these services, particularly when, if I understand it correctly, they offer static images of each browser as opposed to a real-time interaction?

[Groxx]

Design teams that aren't techy enough for VMs, OSes that don't support emulating X (ie, Windows users wanting to test their mobile site on an iOS device), and testing a large number of variations come to mind.

For instance, how long (and how much HD space!) would it take you to set up emulators for all these? http://www.browserstack.com/list-of-browsers-and-platforms (note that these are in-your-browser remote desktop sessions, essentially. some services are static images, like BrowserShots.org, some are not)

For most people, I totally agree, especially with e.g. the IEVMS script. Pretty simple, low cost, and it probably covers all the variety you need, since it's not too hard to install multiple versions of Firefox and Chrome on most OSes. But exceptions exist, and I'd be willing to bet they're relatively large (absolute) numbers.