I just got my second parker FP -- got a 45 Flighter a while back to match the flighter pencil I had, and my mother promptly swiped it from me!
This one is the Mark 1, maroon with lustralloy cap. Some cracks at the screw fitting of the barrel, but nothing bad. Studs on the clutch ring amost gone, it got used a lot.
I rinsed the cap and filled the 21 with water, and it writes just fine!. Sac is a bit stiff, may have to replace it someday, but its OK now.
Still have trouble keeping the pen at the correct rotation to write, I'm spoiled by my Sheaffers, never have problems there, but on the Parkers I keep rotating the pen over and the nib stops writing. Probably habit. I'll have to post the cap so I can tell where the nib is -- between my middle-aged eysight and the hood I can't see it!
Very smooth, nice pen, larger diameter than my Snorkels, but nice.
Peter