As promised, a few words from Steve...............
Rex....it's just as legitimate as any other component company out there without the hype. They mainly sell wholesale but as the retail accounts are thinning out they are selling direct to the consumer like many others more and more. They have been around since the early 90's and are known as a clone company for the most part. But, who cares, so are all of the rest of the large and mid-size component companies. Occasionally they show a spark of originality, but that is rare. Whatever the case, Integra makes a solid product that works well and most consumers truly enjoy. They do stand behind their products as well. And their prices are fantastic both wholesale and retail.
I've used several Integra clubs through the years; still use their Sooolong 460cc Cupface driver from time to time. Only thing I dislike about some of their heads, esp. the FW heads, is the closed faces. If they were square, imo, they would probably be some of the best in the business. (For my game anyway.)