This is the second one I have ordered.  They other lasted a full season before the bulb burned out.  Turns out the cost of a replacement bulb is about 70% of the cost of a new unit.  Since the electronics were exposed to the elements for a year, it doesn't make sense to purchase a bulb and find out the unit is kaput.  It works, I just replaced it.  I DO THINK THE BULBS COULD BE CHEAPER - unless, of course, it is technically better to just replace the whole thing.