Assuming either are trustworthy enough. I wouldn't.
Why not? That's just silly to say. We all have TimeCapsules running so what if something one day go bonk... who cares?
I have used Raid0, Accelsior PCIe, and various PCIe SSD solutions, and NEVER have I had a problem. And if I had, it would have taken me all but 10 hours to restore from TC. I have however had incredible fast drives and easily saved myself hundreds of hours...
I am moving from my MP3,1 with an Accelsior and Raid0 drives installed to the nMP, and have ordered the Sonnet Echo Express III-D Desktop Thunderbolt 2 Expansion Chassis, in-which I will house my Accelsior card (1TB) along with the Sonnet SSD Tempo (Samsung 840 Pro 512GB SSDs in Raid0). That'll give me speed, speed, and speed.