Ask HN: Which post-death messaging service/s are good/secure/trustworthy?

I was reading a post the other day and one commenter mentioned deadmansswitch.net, which made me realize that I should set up something similar. I can see that there are other options, e.g. ifidie.org, safebeyond.com, but I don't really know how or what to check to decide which one is good/secure/trustworthy enough to be used.

For those using something similar, which one are you using and how/why did you decide to use that particular website/service?