These things are unreliable at best. The lamps wear out fast and the transformers that come with them seem to need replacement too often as well. A better option is the Juno track 12 system. Pricier but you only pay once for quality. I talk people out of the pucks and get them to go with the Juno regularly. It is also low voltage so has the same ease of installation, and no wiring spiderweb.
You can get it at most suppliers and I just saw that Lowes can order it. Check it out.
