The Preras do have a tendency to dry out a bit, but for me it's never translated into a hard starter. I do notice though that my inks get darker over time due to evaporative loss.
I've got one of the new Brown Prera and I've not had a problem with it being a hard starter or it evaporating in the least. I actually find it a rather wet and smooth writer for being such a fine nib (writes like an extra fine to me). I've used Noodler's Dragon's Napalm, Diamine Monaco Red, and Iroshizuku Yama-Budo. The pen hasn't skipped a beat.
Those of you who find it dry might try widening the nib slit just a touch using a thin blade, 35mm film or similar.