Testing a used 80-200 f2.8

I just stumbled accross a well priced 80-200, 2.8, second hand, in a major

electronics shop. I've got 14 days in which to return it.

 

It's in good condition, and seems to work - are their any specific tests I can or

should do to thoroughly check it before the 14 days expire?

If the aperture is in good shape (responds well to the 'flick test' of actuating the aperture lever on the back of the lens), I'd say the only other important test is to shoot the lens wide open at various focus distances and focal lengths. You can run the same tests at different apertures if you like, but wide open is most likely to reveal flaws and mis-alignment (and mine seems to spend most of its time between 2.8 and 5.6 anyway).

If it's an AF version, test to see that the AF/Manual switch works smoothly. In one of the lenses I used to use (an AF one touch) the switch would not stay in place, and in another (an AF two touch) it took a herculean effort to get it to move at all.

 

Of course this is just a feel issue, and is not nearly as important as the optical tests that Todd mentioned. And if its cheap enough it probably doesn't matter.