The ESU1808 offers a whopping 18 inputs. Two of these are mic preamps with optional phantom powering and two are Hi-Z instrument inputs. A further 12 are line inputs (four unbalanced on the front, eight balanced on the back).
Eight balanced line level outputs are provided, and you'll also find S/PDIF and MIDI I/O.
Given its smaller size, it's no surprise that the DuaFire offers far less connectivity. It has two input channels that can be accessed via the mic preamp, phono, line and Hi-Z instrument inputs. There are also four line level outputs and a headphone output.
Both new interfaces ship with a copy of Steinberg's Cubase LE 4.0 and are Mac and PC compatible. The DuaFire costs €249, while the ESU1818 is €499.
More information can be found on the ESI website.