I've played fretless off and on for 20 years. (Mostly off, LOL). Recently, however, I've been infatuated with fretless, and have spent the last few months playing them almost exclusively. I presently own 3 fretless basses: a Wal Mark I, Pedulla Buzz, and a '78 Precision, with another one I'm building that will be a fretless Jazz. Each has their own unique voice and character, and each requires it's own approach to playing. I just acquired the '78 P, and it's my first unlined fretless. I love it, and I'm very happy to find it's not as difficult to play as I thought it would be without the lines. Familiarity breeds content, I guess. I know the overall ins and outs of P and J basses, so it feels familiar to me. And that's my word of advice for anyone interested in pursuing fretless who wants to jump in quicker: start off with a fretless version of a bass you may already know (i.e.. Jazz, Precision, etc).