Again, if one searches, one will find that the topic has been debated a lot of times. I have the Piaa Super Plasma Blues, and I like them a lot. They are actually purplish white on lowbeam (quite close to actual hid) and white on highbeams. I have been stopped in traffic in DAYTIME by people asking me what bulbs I was using!
The matter of durability..who knows? I've had mine for quite a while now, no problems. I've heard of others with Piaas using them still after 3 years.