Thinking about (very) low cost scopes for my travel tool bag – travel meaning to the junkyard. I already started packing a battery, because they pull all the batteries (for some reason). That makes moving seats and windows a pain. Who said window handles were worthless?
If by a viewing scope, you mean it lacks a display, you are correct:
...but I always have a screen handy.
I'm not trying to substtute it for a lab bench scope, I have a real scope for that. My thought was that something PCB–sized would be handy for finding out if a sensor actually worked, before buying it, taking it home and finding out it was trash. I agree there is a difference between "working" and "working properly".
I picked up a Hantek 2D72 handheld oscilloscope a while back, a little bigger and more expensive than what you're looking at but I've been really impressed with it. 70MHz scope with storage, arbitrary waveform generator and digital multimeter all rolled into one. It also can plug into a PC and work with their oscilloscope program, I haven't tried that yet so I can't comment on how well it works.