Hi,
We usually recommend AquaC Remora's for hang-on skimmers. Many people get the AquaMedic Turbo Multi as well, which I think is a good skimmer, but it's on the big side for hang-on. We just got in the new Berlin X2 which can hang on as well, but is about the same size as the AquaMedic, so would be a good skimmer, but bulky to hang.
So in what we have, i would say Remora PRO.
That was first time i've heard of the Bermuda. It's pretty strange looking skimmer, but I don't know anything about it. First thought from looks was it was odd design and overpriced, but could be really nice. I'll see if we can get some more info from the manufacture on prices. I think you can only improve that square hang-on design so much though. Bakpak, Remora, Octopus, Bermuda, can only get so much out of that size and shape of a skimmer. Remora did improve on the bakpak.
We should have the Octopus hang-ons in a coulple of weeks. They do have a high demand, but not sure how they compare to remora yet.