Not used one myself, but a friend of my has more than one, and he really isn't impressed with them. He actually talked me out of going out and getting one. I don't think it would be fair to say why, other that he said it just felt weird going through the guides. Flame on...
I have one on my 3wt and one on my 5wt. Not really because I love the line, but because Im cheap and I got them for free with a fly rod at the flyshow. Ive lawncasted both, but only fished the 3wt. They both seem to shoot through the guides and load the rod well, but the ridges do seem prone to dirt which is funny because they advertise it as being almost dirt proof. I havent had the line long enough to say that its memory free, or that or wont ever crack, but from my first impressions its a good line, as good as say rio, I dont think so.
I have not been to impressed with the airflow products that I have tried. The ridge line concept sounds good but how many times have you wound a line on your reel with fingers pinching it and picking off the dirt? ...I have and pick off a lot of dirt or debri (whatever you want to call it) I could see a lot of this debri getting by hiding deep in the ridges on the airflow..but I really don't know and don't think I will invest in one to find out.
I have yet to fish one of the flylines with the ridge but have used the running lines with my speylines and have found it to be the closest to mono for distance and do stay cleaner longer(the ridges are not very deep) and do hold line dressing much longer than a regular line. My association with Airflo has nothing to do with my 2cents on this as I call them as I see them!
love my airflo line....seems to shoot out of the guides well and picks up off the water well.
The question i do have with the line is when i was crazy enough this winter to fish in really cold temps, it seemed to ice up a bit more than other lines, like it had more surface area for the line to attached to