I think that there is NOTHING wrong with buying an infomercial club. They get a bad rap and many people immediately look down on them or pass them off as junk because they are a "as seen on TV" product. This is just a different way of marketing a product (people have the same response to products sold via multilevel marketing -- most are good products just marketed in a non-traditional way).
I have always wondered why a top-notch, recognized designer wouldn't partner with someone who has a good relationship with Chinese manufacturers (I know these guys are out there because I have spoken to one of them) to produce a really good driver or set of wedges/irons and sell them at much lower price. I think the answer is that people automatically dismiss them because they are cheap or don't come from a recognized manufacturer (think good quality clones). The same fate befalls TV products.
Most of the clubs I see advertised on TV are the types of clubs fitters think that many people (more people than are willing to admit) should be playing: shorter (perhaps offset) drivers that focus on consistency and accuracy and not length; thrivers; wedges with more effective bounce; chippers. A LOT of people would do better taking their buying cues from these infomercials than from what players on the tour are using. As with any other club, you have to understand what the club is, what it will do, and not buy into the hype. There's no magic out there -- just clubs that are easier to hit than others.