I've worked for a company that's given pretty much the same two hour on-site test for years, and several times the people in charge of the hiring decisions have forgotten how to do parts of it (it's an open office, I've heard them admit it to the candidates).

It amazes me how they rejected so many people on this test over the years (seems to be over 90% rejections), when they can't keep it straight themselves. Granted they were always busy on other things, but still. Even I barely passed the test.

That being said, they left you alone for two hours while you work on it, sitting in the same environment where other devs are working, which I found much better than some other interviews, the worst of which was coding a full project on a laptop for a platform I haven't worked on professionally in over a year and was a bit rusty on, while one person stared at me from across a desk and a second person stood behind me and looked down at the screen over my shoulder.