[CentOS] Infrastructure HELP!

> Is software RAID 10 decent performance?
>   

depends on the workload.

committed random writes are greatly accelerated by battery backed write 
caches on real raid controllers.    this greatly speeds up things like 
transactional databases.

if your workload is mostly read, software raid performs quite adequately.

with 4 x raid10, you can be doing 4 different reads at once, or two 
writes simultaneously, as long as you have plenty of pending IO requests.