It all depends on your application. If you are concerned about boot times and game load times, then you will not be able to match the performance of an SSD. Applications that require random read or write performance will greatly benefit from an SSD. The seek times on these devices are 100-1000x faster than hard drives. For streaming performance, you can easily beat SSD's though. Good 7200 rpm drives are hitting 120MB/s so 2-3 of them should do. Of course this depends on the RAID level you use. RAID 5 would take another drive to match streaming read performance. I'm on the fence with SSD, holding out for the next gen. I just dont load apps or boot that often, so a few seconds here and there doesnt bother me.