French carrier SFR to give 460€ back when buying an unlocked iPhone

The second largest French carrier SFR is now giving back 460€ when buying an unlocked iphone and a new 24 months subscription plan, in order to keep his best customers.
it seems that SFR doesn't want to get Orange french carrier upset. A french reader received a letter confirming the 460€ reimbursement which didn't even mention the iPhone name.