Hi

   I was wondering what kitchenaid stand mixer you guys use? I see ones with 275 watt 325 watt and 575 watt. Which one do you perfer for a future professional business baker? Please advice. Thank you!

Also, do you guys know if the watt have any effect on the quality of the cake? thanks

The wattage will not affect the quality of the cake but it will affect how much work and how much mixture your mixer can handle.  The more wattage the bigger the motor and the less likely you are to burn it out.  Like anything, buy the best you can afford.

I have a 575 but mostly because it was the cheapest, I got it at Costco. It also has a larger capacity which was a big plus for me.

I had previously upset my old 325 watt KA with some royal icing, the gear housing got chewed up and started spitting out metal chunks. It only cost me about $40 to replace the part but it put me off using it anymore. I sold it and got the 575 watt bowl lift from Costco for about $250.