Hi unenergizer,
For the end user, more choice is always going to be good, and with more competition prices will be driven down and quality will be paramount in the production of new styles.
Obviously style sites that have been around for a long time might look upon new competing sites as a threat, but really if they are confident in the quality of their styles, they've got nothing to worry about.
Every site gets good and bad feedback, its nothing to worry about