@bcantrill is the SVP of Engineering at Joyent. I don't want to put words in his mouth, but I'm guessing he would say that Joyent is trustworthy. He would then tell you to use DTrace.
In terms of trust, I would tell you that trust needs to be earned -- and that it can only be earned one day at a time and that it can be frivolously spent away with a single bad decision. (Trust me that Joyent has learned this the very, very hard way.) So I would say that you should force anyone to earn your trust. That infrastructure is such a trust business is part of why I so fervently believe in open source as a business strategy[1]; companies can change (or be bought) and earned trust violated by a new regime -- but open source can always be forked and its communities liberated from such abrogations.[2]
So while I would (of course!) tell you that Joyent is worthy of your trust (and ask for the opportunity to earn it), I would at the same time say that the open source projects we lead (SmartOS, node.js and -- yes -- DTrace) are the components in which you can have absolute faith.
[1] http://www.slideshare.net/bcantrill/corporate-open-source-an...
Again, my apologies -- and to my point, trust is very hard to earn, and very easy (too easy) to piss away. :(
And yeah, just illustrating how even the best-laid plans of the best of us can't always work out great for all customers.
Anyone remember the "life-time" hosting fiasco?