Soon I will provide my own observations, but I understand that it takes about 45 minutes to get to mash temperature using the 110V system, and another about 45 minutes to get to boil temperature (to save time, it is best to start raising the temperature at full wattage as soon as you start the sparge). The time, of course depends on the ambient temperature, whether the circuit is dedicated, whether or not you are using a brewjacket, whether indoors or outdoors (wind), etc. The brewjackets for the Gen 4 are not yet available, but are expected to be available by this Fall. Based on the Gen 3 versions, the brewjackets make a noticeable difference.
I debated about whether to get the 110V or 220V system and decided on the 110V. I have to boil outdoors (usually in the garage) and do not have access to a 220V circuit outside. Boiling should be no real issue outside during the late Spring, summer and early Fall. During winter I plan to use the Brewzilla indoors just to mash (I don't have a vent hood, but mashing does not create very much steam). I will then transfer the wort to my old boil vessel and boil it outdoors with my propane heater. I will also try using the Brewzilla outdoors during the colder winter by adding an additional 1000 watt heating coil to the boil (hanging from above). This will be plugged into a separate 110V circuit. A friend has used this approach successfully with his Gen 3 Brewzilla.