Fireline is made of dyneema. Always has been. A very reliable and well manageable line for crappie fishing. Up here in the Northeast, we don't have to contend with fishing brush piles and rough structure, so we use the 2# test Crystal almost exclusively. Extremely strong for these applications. You do have to use a fluorocarbon leader with it though - for the abrasion resistance.
Tried Nanofil in 2# test and trashed it after one trip. Same experiene that Ketchn' had. Not even close to the performance levels of Fireline - in my opinion.
"A voyage in search of knowledge need never abandon the spirit of adventure."