I picked up a couple of cheap pens (Yafa - $15 fine point cartridge & Cross Aventura $40 medium point cartridge) about a year ago and I am looking to move to a nicer pen. I like the fine point of the Yafa, but it's cheap, it leaks and the cartridge constantly pops out. The Cross is nicer, but I don't like to wider nib. What is the advantage of a piston pen and what can I get that is nicer with the feel of the Cross? Looking to spend maybe about $50 before I move to the more expensive pens.