Well, now you've opened a can of worms. Using SSDs in RAID is what I call a "religious question." People will argue these points at great length but no-one will get to a conclusion. The arguments against RAIDing SSDs are 1) using RAID cuts off the TRIM command, so drive performance will degrade over time, and 2) If you buy the twice-the-size drive in the same product line, the manufacturer will be using twice the channels anyway, so RAID0 is not only risky but pointless. Against point 1, people now argue that Garbage Collection is good enough to be sufficient.
The answer to any good question depends on the conditions. In the abstract, SAS is "better" than SATA. In context, I don't use SAS. It's designed for server environments, with the major points that I am aware of being dual-porting, which allows the drive to fail over to another server if the primary goes down, and the huge number of devices that can be attached to a single port.
In practice, whether or not SAS is better for you depends on your application. I am not aware of any advantage of SAS in the home / hobbyist world, and it adds a significant expense. My personal take is that there is no advantage to SAS in my hobbyist world, considering that I am not building (as some hobbyists do) a cluster or server. And I do have SCSI devices; there is an Ultra-320 SCSI controller in my PC right now, to connect to my RAID array.
So the main question is: What exactly are you building, and what will it / they be used for? And my question, out of curiosity, is: What motherboard have you got that has both SATA and SAS ports? Or are you at the pre-buying stage?