the ubitx was certainly designed for the op of humble means, including youth. perhaps us hobbyists have purchased many of them. it is an amazing rig overall. okay we can wonder if 0.1 uV is exaggerated or more likely the designer has excellent hearing (-: The receiver clearly was designed with dynamic range in mind. I expect it hears most everything my K2 hears in most bands. As delivered the principle need is BFO alignment.
most of our HF receivers from the past several decades likely have similar sensitivity - its other parameters where they separate. nonetheless I have numerous CW contacts with my ubitx and I am amazed how well it does on SSB (I got fortunate I think in the particular microphone I found in my leftover stash).
my ubtix v4 was delivered with a potentiometer, but I also purchased an enclosure kit that contained pots and controls. my unit does not have an of-off switch in the volume control, so I don't recall if the stock volume pot has that feature. my power switch is a push button in the back - I suggest finding whatever power switch its op will appreciate.
does the ubitx in your hands have a commercial looking enclosure? many came from amateurradiokits.in. Sunil the proprietor would certainly fill you in on the pot, but it might be difficult to source that particular pot in DL.
okay this list may be biased but the ubitx is a nice radio adventure. when we have sunspots again, I am imagining lots of folks enjoying it when its their primary rig. I have plans to set mine up for WSPR reception. nothing like this anywhere in its price range - but someday watch for the QSX when it emerges (more assembly required).