emr50- i bought my 80/100 watt bulbs from capitolwest. the manufacturer was "heliolite" they have some xenon gas,there is not the yellowish effect i had with MY 55/60 watt ones.
i have been very satisfied, and "knock on zebrano wood" i've not experinced any problems.
imho piaa bulbs burn a lot hotter and are WAY overpriced, just not worth it.
my 80/100's really seemed to kick them up another notch!
*92 400e 124.034, SOLD
*92 300e 124.030, SOLD