Many people shop at fasttech. It does take extra time to ship (Up to a month, most experience a 2 week transit though). Unless the item says it is authentic in the title, it is a clone - fasttech does have authentic items though, but you will see it in the item title.
Whether an item is any good depends on the item. Check reviews, check discussions (both clearly listed on each item) to find out what other users have experienced with each item. That is your best way to gauge if an item is "any good". I have personally had good experiences with fasttech, but I am very thorough in my research on each item I buy.