I have gotten $100 worth out of it in under two weeks. I love it. I love all u-he's stuff, but this has quickly become number one! Plus, basses, arps, leads and even some pads are monophonic by nature, so being monophonic is really not as limiting as you might think. And I imagine you already own oodles of polys, as do I. What you're paying for with this is character, and it has it in bucket loads. And frankly, I actually like being limited to monophonic in a lot of cases. It forces me think in a different way.
And lastly (this should be the kicker for any fence-sitters out there), word on the street is that Repro-5 (a polyphonic synth based on the Prophet 5) will be free for Repro-1 owners.