Our 8.5KW shower is on its way out and we are thinking of replacing it with a 10.8kw due to current one having such a poor flow rate when heated. How much of an improvement would we see by upgrading it to a 10.8kw? As we will need to have the cables changed we are weighing up the options of upgrading vs getting a power shower installed. The flow rates are as follows with 8.5kw: - Cold 8 liters per minute - Hot (ideal shower temp) 4.2 liters per minute Would the more powerful 10.8KW shower be able to knock out 7+ liters per minutes at a hot temperature or would it only be a small improvement on our current one? Also if anyone know roughly what we are looking at to have wiring upgraded from 6mm to 16mm would be great to know. Thanks in advance.