Of course, I'm talking about real RAID controlers, not FakeRAID (which are just bad software RAID). For the HW vs SW, it depends on a lot of stuff, both have advantages, but HW RAID with a good controler, good write back cache and a BBU will always have better performance. Anyway, here, we're talking only about the /boot partition (because actually /boot is always made as SW RAID in SME9, no matter which option you pass to the installer), for which performance is irrelevant.