Infoserv,

Yep we definitely offer custom hardware configurations including various RAID levels. (0, 1, 0+1 10, etc) and hot-swapable hard drives are certainly available, we run them on some of our own machines now.

Zero downtime is virtually impossible especially with only a singular machine. Even google itself has gone down in the past. You can cut downtime by using multiple machines to help deal with hardware issues.

We offer managed hardware load balancer services for people that need multiple servers to power their applications.