Knownhost vs. Namehero vs. A2

I can not trust Knownhost, because its owner Chris used to be the owner of K-Disk.net at once, he sold it to a large company.
The new property of K-Disk.net terminated my accounts without notice.

For Namehero, I've been using them for a year. They are good with everything, the only problem that I face is that they only allow 25 emails per hour per domain.