BBU still needed with SSD?

Hi,

Is BBU still needed with SSD?

SSD has its own cache. And in certain models such as Intel 320 that cache is backed by capacitors. So in a sense that
cacheacts as a BBU that's backed by capacitors instead of batteries.  

In this case is BBU still needed? If I put 2 SSD in software RAID 1, would that be any slower than 2 SSD in HW RAID 1
withBBU? What are the pros and cons? 

Thanks.

Andy