It's worth noting that for around the price of the "4S" upgrade kit, you can similarly add a CHT nozzle to the Bambu Lab printers (e.g. the official E3D Obxidian nozzles, or a Revo nozzle and the Biqu Banda Revo hotend replacement, or a generic hotend with an M6 thread). The Obxidian nozzle - the only one of these I've personally tested - can push some really absurd flowrates, I've gotten up to 35mm^3/s for some generic PLA out of the 0.4mm nozzle before flow artefacts started to occur, and 25mm^3/s for PETG.