The first 'get-your-unlock-code-here' service I tried spent 48 hours digging for my code and came up empty. The notification email implied the null result was my fault, and they suggested I follow the IMEI fetching instructions more carefully before resubmitting my order (LOL). The second service was more customer-centric and professional, but couldn't understand my frustration over the blunted options for 'device model' on their submission form (my Xperia Z1 C6906 was simply 'Xperia'). Two days later I was officially informed they couldn't find my code, probably because my phone was just 'too new', and I'd need to fork-out another $30 to have them dig deeper.
Technically, CellUnlocker.net was my fourth attempt to solicit digits from a code-harvesting service (#3 was the dumb-as-a-bag-of-crushed-rock csr in the Rogers Plus retial store who met my network-unlock request with a vacant look and straight silence... lol). Anyway, $8 and less than 4 hours is all it took CellUnlocker.net to crack this nut - they literally prevailed where so many others failed. Highly, *highly* recommended.