What Riglol does is generate the same codes you would get if you paid to buy the upgrades so there is no actual 'hack' taking place on the scope itself, all you're doing is entering code(s) that are correct for your scope.
If Rigol issues new firmware, the scope will work as before; if it didn't, Rigol would be hobbling all the buyers who paid for upgrades.
FYI, after the bandwidth 'upgrade', the DS1054Z will report itself as a DS1104Z under system info.