The mascara's pros are its uniquely structured brush which allows for very, very long lashes and virtually zero clumps. The brush has comb-like fibers rather than criss-crossed fibers. As a result, it is a great brush to use both on the upper and lower lashes. It is possibly the only mascara I have used that didn't result in clumps that I have to comb out myself.
The cons? Well, I wouldn't really call it a con. Since my own lashes are quite sparse, I generally prefer a mascara that thickens. The brush's comb-like structure, however, doesn't allow for much volume. Yet if you're looking for a fantastic lengthening mascara that applies smoothly, this is definitely your mascara.