Can confirm that the Bell Z2 will work with Wind Mobile. I unlocked mine and now switched providers. Took a few minutes for the phone to register to the Wind Network even after manually looking for it but it did work.
Here are the APN settings I used to get data and mms
internet
Name: WIND CA
APN: internet.windmobile.ca
MCC: 302
MNC: 490
APN type: default,supl (it is important you change your apn type here)
mms
Name: WIND CA mms
APN: mms.windmobile.ca
MMSC: http:-//mms.windmobile.-ca (with out the hyphen, website wont let me post url's)
MMS proxy: 74.115.197.70
MMS port: 8080
MCC: 302
MNC: 490
APN type: mms