The difference is, other hosts will crash under load and you'll lose all your requests. Mosso is like a train and other hosts are motorcycles. It's slower but can haul way more tonnage.
I run two such accounts starting several months ago. I'm infuriated by some quirks of their site management system,* but the reliability has been good. I think they've gotten better.
* Especially: It's impossible to move a site from one account to another, or even from one client to another client in the same account, or even from no client to a client in the account. Impossible. They can't/won't even do it for you on the backend.
Compare to telling the mail system that your mail is somewhere else. DNS you can do yourself, mail server you have to ask them to do if you want other mosso users to be able to send to you. That's a reasonable compromise IMO.
