Front cheek implant vs fat transfer for cheeks?

I see a lot of clinics offering front cheek implant. I assume this means submalar implants. I've only found one review of someone who has had it done on Realfself, and they deleted their post. I also don't see many before and afters. Has anyone had this done?
It seems like most people go for the fat transfer for a flat, sagging midface. But a permanent solution sounds a lot better?