Been quite impressed with ours, and as a keen cyclist it's a much better ride experience than the Bafang alternative. We're coming up for 500 miles and it's doing well pushing a heavy long-tail cargo bike around and over some decent sized hills. From reading around it seems most performance issues (not that I've noticed any beyond the cadence limitation and occasional hunting) can be resolved with the open firmware, which is next on the list after the lights. As for failure items (blue gear, sprag clutch, etc.) these are relatively affordable and easily replaced.
Our bike is a daily runabout and spends a fair amount of time outside schools, shops, friends houses etc. so having to take lights on and off the bike at each stop is a pain in the bum and misses an opportunity to run them from that nice big 48v power supply. If left on the bike then at some point they'll get swiped by opportunistic scrote.
Mine has been unreliable out of the box, unlike my three BBS02 builds which are rock solid.
As you say things are better with OS firmware, unfortunately I'm not willing to brick the controller messing about with the unknown. Looking on Endless Sphere, even the OSF is not without issues?
Must admit I like the torque sensing, but the TS is just too unreliable and poorly made for my liking (maybe its just my unit?).
Issues with mine after less than 250 kilometres.
Display alters assist level by itself. One minute going along nicely in say level 3, next thinking this is hard work, look at display and it is on level 1?
My fully charged Jumbo Shark 48V 14.3Ah gives 54v. The TS will not start at that voltage, so have to put it on another bike with a Bafang to burn off some volts before using on the TS! That is pants!
The crank bearings have developed about a 1mm play in them. After this amount of mileage, that is poor and does nothing to inspire longevity.
I will not buy another!
very low current under 3watts dim to useless 
