Happy with product and a few reviews said that htey blew quickly. I'm a trained mechanic and have had them in a focus for over 6 months with no issue. With these types of bulb touching the glass element severly affects the lifespan of the bulb, I fitter wearing latex gloves and using tissue (recommended way) and there fine. I'm not saying every buld will be perfect but I'd expect most of the "Don't last long" comments are due to incorrect fitting practices - i.e. touching glass.
Not a bad product and generally happy with purchase as was less than £10. Was bought as a stocking filler for christmas but the quality is not great. Its been on the back of my sons door (as its designed to be) but the brackets snapped quite quickly. Still happy as it did the job it was bought for and lasted a couple of months as with all christmas presents