The ones from silicawicks dont fray and become bits, it just doesnt have as high a temp resistance like the ceramic silica like the ones on the bottom photo. The german one I get is not as tightly wound, but it has a real high temp resistance about 1000 centigrades which is 1862 Fahrenheit. If I torture the silicawicks silica like I do the ceramic silicas it does not hold up over a few seconds . I just flame it lightly to burn off any left over coatings after the boiling I do to all my silica. I dont think its bad, just not as tuff. I guess Ive been spoiled by the ceramic silica's. I have had some that came with atties that cant even hold up to light flaming and some that came with an expensive atomizer that was soooo flaky that just touching it gave me splinters and cut my fingers and came apart almost like a dandelion. Stay away from those. Ive seen some sites that sell fibreglass wicks, now that would be a no no, wouldnt it?
Please let us know where you got the bottom picts ones, those look like ekowool and I cant seem to find it where I dont end up paying just as much for shipping.