Before I even got a chance to power the scope on, my cat "G-man" was all over the box situation:
Very happy to see the ref signal with considerably less noise on the Siglent SDS1202X-E than the Hantek DSO2C15 (photo rather than screen dump on the Hantek because it kept corrupting my USB stick). This was deliberately setting the trigger point low to catch the biggest noise dips.
With the Siglent, there was no noise at that level to trigger off, hence the different trigger position in the comparison.
I know this is apples/oranges comparison when one scope is twice the price of the other, but one I can work with, the other I can't.
Of course the Siglent does pick up *some* noise but it is more intelligently displayed - it appears that the longer capture points are compressed down into the screen width and where points accumulate in that pixel bucket they increase the intensity. So noise is visible as little "hairs" but not as brightly as the rest of the signal. The Hantek just seems to decimate the source signal to sit on-screen. It could also do this (at the cost of processing time to update the display) with the right software, but doesn't at the moment. It is subtle differences like this that make for a more professional experience.
I do prefer the Hantek's button layout, tactile feel, appearance and silence (though the Siglent fan is more a gentle air movement noise than a whine). But that's about where the preferences end.