Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Big on size, small on reliability

A friend of mine bought this mixer with the intended use of mixing mostly double-batch cookie dough.After less than a month in use, it appears that the speed controler has gone south. The mixer starts, runs 2 seconds and shuts down.She owned the 4.5qt previously. I own the 325W 5qt model. Both of these have been workhorses (i have been mixing bread dough in mine for 10 yrs - albeit infrequently- and have 'abused' it more than once.)General Pros of the Professional 6qt model: Large bowl, double-batch capacityCons: noisy, unreliable, too big for small batches, takes a lot of space.as much as i love my 5qt model, i would turn anyone away from this larger one. If you make bread in large batches, consider a Bosch or Electrolux unit instead.This model also appears to be over-represented on the refurbished/factory serviced market.