I have used my Bosch mixer in a semi-commercial application for about 6 years. It's power is amazing and easily handled making 10 pounds of fruit cake at a time. The meat grinder easily handled beef, but had problems with the membrane in grinding wild meats. There was never a question of it over-heating even in grinding 10 or 20 pounds of meat at a time.
However, I found it to be cumbersome when making large batches of cookies - having to put the cover on and off between processes was a pain, so I've purchased another KitchenAid mixer (from which I had 'graduated' to the Bosch), for day to day use. I find it much more convenient, and certainly strong enough, for mixing up cakes or cookies. It seems a little silly to have the two machines around but convenience makes the day go better.