What’s your opinions on blade vs brush cold smoke seals?

Most doors I’ve inspected, the blade seals always seem to fair worse over time. They seem fair less robust than brush seals. 
Is there any benefit for a blade seal? 

In my experience the brush is certainly more durable but the blade offers less friction so as to allow the door to self-close more reliably.  Have a look at this  https://www.ifsa.org.uk/documents/  you might find it useful at some point.

I see far more failed blades/fins than brushes, they just don't seem to last and are easily ragged, ripped, chewed, stripped, perished etc. My personal preference is brush seals