Over the many many years that I have been with Silverlime there have been various outages here and there and for the most part they are rather short outages and not too frequent.
But as another reviewer stated, if there is a long term outage they are impossible to contact. Calling them gets you an answering machine which seems to be ignored as I have requested callbacks on several occasions and received no calls back.
There used to be a way to contact them via AIM but are never online anymore.

There are better services out there that are less expensive and give you more and have better customer service skills than this company but I have stuck with them partially because I'm lazy and don't have a lot of free time to deal with the upload to a new host server and partially because I appreciated Brock when he was there. Brock was the ONLY reason it seemed anything got done. You could contact him almost any time and he would return emails, phone calls, and IM's. Now it's like they don't even care. Even their own website is currently down along with their entire customer base.