Coltene is an excellent company to get your start in dental sales and distribution. They have a broad range of materials and products that allow the rep to call on any GP dentist, endodontist or dental lab. They don't offer nearly as much for ortho, perio, or OMS.
Success is largely determined by the relationships you cultivate with distributor reps. Like any other manufacturer position in dental, hitting your bonus depends a great deal on new product launches.
My experience with getting "annual" reviews was that I had to come to them with another job offer before they would consider a review or raise. This was not an effective management strategy.
Their training is excellent as is their car allowance (at least when I was there years ago).