Yep.. good information here.. only one thing to note on the weights.. for a long time UR listed a higher weight until other pulleys came out, and theirs somehow became lighter all of a sudden.. I don't think I've seen anyone weigh them to see if the numbers stack up.
That being said, you definitely want to make sure you purchase a pulley like this from a reputable source, and definitely do not risk going cheap, especially eBay or some off brand.
These are extremely precision machined and balanced in the design, and not something you'd want to chance to the abilities of a potentially sub-par mfg.
In regards to the harmonic balancer debate, this has been discussed at length in other threads.. long and the short of it.. no the crank pulley on the VQ's is NOT a harmonic balancer, the engine is internally balanced.
But certain things are a must.. like a stainless steel ring to prevent wear, should have stock timing marks.. etc etc etc
