How are you going to chill the keg, do you have an old fridge? Remember the beer carbonates better when the beer is cold, below 6 degrees. I normally leave my keg in the fridge overnight before gassing.
Had a look at The Brewie website and i have to say it looks like a very expensive kitchen appliance. For the money you would have to spend i think you would be better off with a Braumeister, Grainfather or somthing similar. I use the grainfather and make some great 19L batches for my kegs...