As always: what would you like to analyse with the scope?
Do you need in depth math functions?
Digital signals, so I need possibility to capture some long sequence, and then analyze it, zoom, find noise/strange edges.
I need long memory for this and interface that can zoom by mouse click (or something more suitable then changing time, scroll by encoder, and aoom in again, like I do now with OWON SDS8202).
Analog signals, for example, response from gamma-photons, ~50-500mV, with possibility to see them with signal persistance. With my current scope such signals not so far from noise floor, so trigger works not so good as I want, persistance works not very well too. Ideally, I want to get hystogram of amplitudes of signals was captured by trigger.
Digital signals, like PWM, with history/trend view, to see, for example, if PWM period was changed over time.
I was very impressed how measurement values displayed on Magnova (on oscillogram itself, showing what I see instead of several columns of values in table separated from signal view).
And, finally, I cannot understand which features I will like, I had no expensive scopes yet