Don't bother with the Chinese stuff, the UI is horrible, especially on scopes with a shared vertical control knob.
Have to agree that a shared vertical knob would be a huge mistake. Happily, only the very cheapest scopes do that. There are plenty of very reasonable options from virtually any manufacturer that have dedicated control sections for each vertical channel.
While we're discussing UI's, one thing I do NOT like is a touch screen. Just has no place on a scope IMHO. When I reach up to the screen, my finger and hand are obscuring the thing I want to be viewing. Plus you're always smudging the screen with whatever is on your fingertips. On some of the "laptop-scopes" a touchscreen is almost a necessary evil to get the screen size in a reasonably sized package, but on a real scope you should be able to adjust the settings while watching how those adjustments affect the display. And to top it all off, a touch screen generally costs more - you are literally paying more money for a worse UI, while adding just another layer of unnecessary technology that can break at some point and disable your expensive scope.
Yeah, I know... touch screens are easier for specifying certain specialized trigger events. Fine, if you want that, make the touch screen an option for that purpose. But don't force large portions of the UI onto the touch screen "just because it's there". Unlike smartphone fanboys, Engineers are trying to get real work done - not impress their friends with multi-finger gesture sensing ("Cool, the latest scope is down to just one 6D joystick!!!"). Touch screens improve a few things, but they're not the de facto answer for everything on an oscilloscope.
This is my $0.02, worth exactly what you paid for it, YMMV, opinions are like you-know, standard disclaimers, etc. No offense intended if you feel differently, buy the scope you prefer and I'll do the same! {grin}