You could make a software check / dump part of the support / RMA process. 'Put this on USB drive, insert in product, record information on display' type deal. If the check fails to work, then a dump of critical software could be done to determine if the problem was due to 'official' software or not.
"What if" .. the modded firmware is so bad that put the scope into infinite loop once booted ?
Assuming they released "all" including the boot code, and the user screwed the initialization code so bad that made the scope just sit there doing nothing in the deadly infinite loop.
When its time to RMA, and as usual, "few" users

will be pretending innocent, and as expected, the
fight dispute between seller and user on RMA ... and so on, you just need a little imagination to think of the next scenes.
(Posting a process to 'un-brick' the 'scope for those who do manage to do so shouldn't be too hard.
"What if" .. the un-brick process only can be done if the initialization code also is not modded, and alas, because of the low cost constraints, design wise, protecting the init code is not possible.

It shouldn't be possible to physically damage a 'scope via firmware -- so far as I am aware.)
"What if" ... the modded firmware is so shitty, forgot to switch the front end relay to switch to less sensitive input level, while the screen is prompting its ok to plug and pump in high voltage signal ?

... another "what if" ... the over temperature mechanism is triggered, and the part of the firmware that supposed for handling the shutdown sequences is ignored or buggy ...

Too many "what ifs" ... and back to my previous post, its never about these "what ifs" scenarios anyway, the "fact" is, these scopes are selling like hot cakes, so why bother ?

Rather than sink deep in this fuss and mess, why not focus and concentrate on designing and making another new generation low cost scope, sort of DS1054Z successor, as DS1054Z is considered quite old now, and the new beast is specifically targeted to hit very hard to those new competing products.
