I've seen it stated in many places that it's useful to have both an analog and a digital oscilloscope. Does the same hold true for function generators? Are analog generators better at non-sinusoidal signals? I've read that digital generators drop the max frequency when you get into saw tooth and other functions. Lastly, how do I determine how big of a frequency range I need? Do certain areas of electronics require GHz freqs while other areas are fine in the low MHz?