Like or dislike?
I love the way they look...I use mostly Kreinik and Petite Treasure Braid. My favorite is the PTB, but there are so many colors in the Kreinik. and they add so much especially to Miras, Passione Ricamos and Joan Elliotts.
One thing I did figure out. It is wise to keep a separate needle for metallic threads and one for the DMC or other cotton you are using (or silk). The metallic thread can rub a barb on the eye of the needle. If you use the same needle on cotton, etc, it will shred the fibers. I try to keep a separate needle for each.
So do you prefer a specific metallic, whatever they say, or skip it all together.