The new RVP (Coleman) Mach 8 units have 2 motors rather than the single dual shaft motor found in the Penguins. The condenser fan (outside blower ) has a separate and different motor that the evaporator fan (indoor blower).
The fan characteristics are different also. The condenser fan is a bladed fan while the evaporator fan is a squirrel cage. The outside sound level
of the Mach 8 is definitely above that of a Penguin, but the inside noise
is lower than that of the Penguin.
Both units are covered by an initial 2 year warranty, but Dometic has an available 3 year extended coverage that provides replacement for an additional 3 years and labor coverage for an extra 2 years. RVP has a similar program, but after the initial 2 year warranty, they will usually insist on repair of the unit rather than replacement.
There are other features that differentiate one from the other. Let me know if you are interested in these.