[Keith Henderson] “Another train of thought would be, why upgrade the Z150 with Z90 specs”
True. Some might want the Z90 in a larger body. Of course they may add even more feature to a newer model but I can’t imagine what those would be. It’s quite possible the Z90 will lead in features for a while.
Looking at recent history, the X70 came out in late 2014. The Z150 came out in early 2016. The Z90 (same body as X70 but with new features) came out in late 2017 (or early 2018). So it’s possible the Z150 wont be updated for another year. Each camera may be updated every 3 years or thereabouts.