You can use your own modem. Just tell them the MAC address and serial number and it'll work on their network.
As for the promotion, you essentially are getting a free modem. You pay $99, and you receive a $99 credit on your Rogers account. Why would you go out and buy your own?
TBD ... that is assuming the person you talk with will bend the rules. The rule has been that the modem must be one that was sold by Rogers, or through a Rogers authorized retailer. All those modems were in their databases. Getting a modem added has USUALLY been impossible, unless you very fortunate (for example, you knew someone at Rogers who could/would add your modem to the register).
·