Which KitchenAid mixer is the best to buy?

It depends on your specific needs and preferences. The KitchenAid Professional 600 Series 6-Quart Bowl-Lift Stand Mixer is a popular choice for heavy-duty tasks and large batches of ingredients, while the KitchenAid Artisan Series 5-Quart Tilt-Head Stand Mixer is a more affordable option for everyday use. Ultimately, you should consider factors such as the size of the mixer, the power of the motor, and the number of attachments available before making a decision.