Hobby or Peregrine?

Hello, 

The flock of 30+ goldfinches that visit my garden were chased off today by a small bird of prey that was either a hobby or a peregrine. It had the same black/blue moustache pattern, was kestrel sized and had very pointy wings. It had pretty strong wingbeats but short wingbeats but was swallow-like when chasing. I didn’t manage to take a photo as it happened pretty quickly. My book doesn’t make it much clearer. Does this behaviour and description wise sound more like a hobby or a peregrine? 
Thanks