Most of the cheap, low wattage, LASER pointer modules, from China (where you'll find most come from), are just as good as anything that you'll find offered by the large parts houses (like DigiKey). They are so much cheaper because, labor is much cheaper there, raw materials are much cheaper there, the Chineese government subsidizes the export industries to build up it's world economic position. The quality control was an issue not too long ago, but that is getting better as time goes along. Where do you think DigiKey is getting thier modules?? They don't make them thierselves.
Check out Laser Pointer Forum for more info.
And the above caution about DPSS modulea blasting out IR is very correct! But, if you want low power Reds, no sweat, no danger.