mine was mapped on super unleaded and on the rare occasion i have put 95ron in (due to there being hardly anywhere round here that sells super) i can tell straight away because it idles like sh1te. and my det alert will flash if i go on boost.

occasionally i have had sh1t quality "super unleaded" from the likes of Jet, and experience the same symptoms as if it is 95ron (in which case i keep the loud pedal to a minimum til i get some good stuff in)

you'd need to be 100% confident in the mapping, the build of the engine, IAT's, all the sensors blah blah to be able to blaim the fuel fully.