Foster/Zanonti TCU Condensing Units

Hello all just after some info on these condensing units and wondering if anyone here does any installs for Foster Coldstores and has come across these particular units, i have done two of these so far TCU6-3L and TCU3-3L and have found to be a quite interesting unit in there great performance, looks (well as far as cond units go)

Although i have come across the 6-3L to be pre-charged and the 3-3L not to be pre-charged with R404 but with no id on data plate to confirm the 6-3L to be charged or with how much???

Anyone come across these unit and have any experience good or bad would be good to find out others opinions