what are the differences between miche primato and primato advanced cranksets,
also if I had miche primatos would sram omniums be a considerable upgrade
the upgrade from Primatos to Omniums mainly gives you the benefit of being able to use more common 144bcd chainrings on the Omniums. There are a lot more chainring options for 144bcd than for 135bcd, so if you're racing at the track, changing gears, and sharing gear with teammates, that comes in handy.
Omniums are probably stiffer, in part due to the external BB, but I don't know how many people are reaping benefits from that.