One possible 'gotcha' is that, for some op-amps, there's a limit on the voltage difference that there can be between the two inputs.
Normally, this difference is kept at zero by the action of negative feedback, but if you're clipping the signal, then this isn't the case.
Often there's a pair of back-to-back diodes (or something electrically equivalent) between the two inputs, so if you get more than about half a volt between them, the input current will increase sharply.