Posted 11 October 2017 - 16:45
I've got a diamond 580 (not AL) and 3 ECOs - no flow problem with any of them, even the one with the 1.5 nib. Having said that, the 1.5 is on an ECO and their designs have improved over time, plus they did change nib manufacturer between the 540 and 580 (think ti was that period), which would also mean new feeds, which could have made a difference.
The only issue I have had so far with my 580 AL is that the piston does not got all the way down to the feed. I got an air bubble and couldn't get the ink to flow when I refilled the pen with distilled water to try flushing the ink. Someone in my local pen club said that this was a design issue -- but between us handling the pen when I showed it to her we were able to either break up the bubble or move it around in the chamber enough that I was able to then write again.
Oh, and when I did flush the pen finally, I now have some discoloration on the section from soaking in ammonia solution. But that's just cosmetic, as far as I'm concerned. Still would not buy this new LE pen, but that's strictly because of the color.
Ruth Morrisson aka inkstainedruth
"It's very nice, but frankly, when I signed that list for a P-51, what I had in mind was a fountain pen."