score:7
Although originally advertised as such, to date there seem to be no luggage deposit service at Torino Porta Susa. Indeed most queries for deposito bagagli Torino Porta Susa
return negative answers. The Ialian Wikipedia page on Torino Porta Susa does not mention left luggage service. This newspaper article also confirms this:
Piccola pecca: la stazione super tecnologica, celebrata come uno dei fiori all'occhiello della città, non ha un deposito bagagli. E se si fa viva una viaggiatrice a chiedere lumi su come fare con zaini e valigie al seguito, la risposta di chi lavora in stazione è: «Non è previsto un deposito bagagli. Se proprio vi serve rivolgetevi a Porta Nuova».
The Man in Seat 61 is also correct in stating:
There are no left luggage facilities at Milan Porta Garibaldi or at smaller stations including Florence Campo di Marte, Florence Rifredi, Rome Ostiense, Turin Porta Susa, Civitavecchia, San Remo, Livorno, Lucca, Siena (though the nearby bus station has a facility), Montepulciano, Modena, Ravenna, Peschiera del Garda, Orvieto, Rimini, Brindisi, Lecce, Taranto, Reggio di Calabria, Salerno, Siracuse, Pompeii, Sorrento.
This guy even wrote a letter (in Italian) to the mayor, pointing out the lack of luggage storage in Porta Susa. The mayor replied stating that it's a matter of security. I am somewhat doubtful since Torino Porta Nuova does have a left luggage service.