Luxeon and Other 'Stars'
'Stars are an established technology. Originally Luxeon Stars, made by Philips, they are now made by other manufacturers too. It's unlikely you'll detect any difference in the light quality but it's probably okay to assume that reputable manufacturers produce more reliable and consistent products.
One watt 'stars' (which we supply) are at the lower powered end of the range, they can also be bought at two, three and five watts.
They need a stable current of usually 350 mA. If your voltage is liable to spikes then you may well blow a 'star' if you try to wire them with just a resistor in line.
The best way to produce a stable current is to use an LM317 as a Current Regulator.
When running 'stars' at anywhere near their peak performance, the 'stars' and the resistor (or LM317) get noticeably hot. If you are using a resistor by itself its best to use a 6 watt or even 10 watt resistor so that it doesn't get too hot.
If you are using an LM317 this will get hot, and you need to mount it, as well as the 'stars', onto a heat sink. This is a piece of metal which conducts the heat away from the 'stars' and other components and allows it to dissipate. Jam jar lids are a good cheap recycled solution....!
Wiring up a 'star' is simple. Looking closely at a 'star' LED you will see 4 shiny metal pads. These are where you connect the wires. There are two '+' and two '-' pads but you only need to use one of each.