I lost a hard drive initially but I was fine with it because it was my choice. I bought a new one and waited for a newer build and continued. I don't mind because my testing is on a laptop which I don't really use much. I'll use it once a month if not less. I do everything either on my desktop or phone.
But you mention you have done all their technical previews? From my understanding this is the first time Microsoft has ever done a technical preview. The older OS's had beta releases. That's not the same as what Microsoft is doing here. You are getting it as it is getting built and right before your eyes. And they have made this clear. This is why I think people getting into technical preview should have to read the terms and then take a test on it before they can join.
This is not MIcrosoft's Fault!
By your understanding if the very last build that I get right before rtm, and it is still giving me problems, I should just sit on my *** waiting for someone to solve that ****, which I am not supposed to face in the first place.
When I first bought Lumia 520 in 2013, I suffered several random reboots, crashes, duplication in song bug, and many more I don't remember now. My point, as a customer of Microsoft's OS, I didn't expect those bugs and certainly I wouldn't want bugs when I upgrade from windows 8 to 10. Therefore the purpose for each of the insider should be, to make sure the final product is bug free and has fluent experience, be it a technician, engineer, student, artist etc. And no matter how they have tested it, given caution to the obvious bugs, overall, should have a satisfactory experience.
Also,I am grateful that Microsoft has launched such a program, but I needn't to be reminded of just for sharing my opinion.
P.S. I tried testing on secondary devices, but never could give enough time, ran both the versions on my primary, and only recently(10122 and so forth) experienced work affecting bugs that prompted me to revert back.