Postgresql data integrity during RAID10 drive rebuild

I need some input from the Postgresql community.

Our animal hospital runs Postgresql 7.4 on a 6-disc RAID10. The database
logs are on a separate RAID1.

We're using an LSI MegaRAID 320-2X controller. The controller reports one
146GB SCSI disc has failed in the RAID10 performance is in "DEGRADED" mode.
The database seems to be running fine but slower.

I've never had to replace a disc in an array with Postgresql running on it.
LSI says I can replace the disc and do a rebuild while everything is
running. I am of course concerned about data integrity/corruption.

Has anyone had to rebuild one of their disc in an array of their database?

Thanks for your help.

Steve Poe