It's always good when your outlook is positive on checking out a new instrument.

What you might try, if you have the ability to create such a wafeform, is to stimulate the 'scope with a 100 Hz 1-volt p-p sinewave to which you add a 10 MHz square wave with a 10% duty cycle and 10 mV amplitude. See how it triggers when you're close to the 500 mVolt level, and then see how it does close to the -500 mVolt level. It will probably do just fine. Try decreasing the amplitude of the square wave until the thing won't trigger reliably. You can tell that the triggering is getting close to dodgy when the main signal becomes less crisp and clear, as it then is triggering on different parts of the square wave's rising or falling (depending on how you set your trigger) edges. At some point it will probably become quite "muddy", indicating that the trigger is somewhat ambiguous, and that tells you where it breaks down. It'll be interesting to see how it behaves, and whether it handles the waveform equally on both phases of the slower wave. You can probably create this waveform pretty easily using an old-generation mixer, e.g. NE602 or NE612.

Rather than trying to find the obvious performance limits of your 'scope, I'd first attempt to verify that it meets all the published spec's. Different manufacturers take different license with respect to interpretation of things such as rise and fall time, bandwidth, etc. It's important to know what these are, so you will know what's going on when these limitations appear in your measurements.

It's important to know what your instrument "does" to what it "sees". Whereas it's nice that your instrument often will exceed its published spec's, it's much more important to know how well and how accurately it represents what it is supposed to represent.

RE