I'd assume that boot times is better with a SATA drive since the PCI startup takes some extra time. My experience is that a macbook air is much quicker to start than a "barebones" mac pro with an accelsior (I have a 2008 MP with an accelsior, takes rather long time to start up compared to when I had a samsung 830 in it). It's not "HDD"-slow, but still, slower than a normal SATA SSD.
But after boot time it's amazing.
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Carbon Copy Cloner, similar software to Superduper!