Question: I’m looking at getting a Crucial M225 SSD. Now the question that’s on my mind, is is it worth RAIDing these things? In fact are there any RAID downsides particular to SSDs that you don’t see with typical magnetic HDDs.
For 10% more, I can get 2x 128GB drives over the single 256GB drive. Now bare in mind that the 256GB drive has got about 5-10% better performance than the 128GB one.
Answer: I would definitely get the single, larger drive. It’s unlikely that RAID-ing two smaller drives will provide a useful performance increase, and the TRIM command (which helps preserve an SSD’s performance over time) probably won’t work.
The SSD’s controller should also use any free space to help maintain performance and maximise the life of the drive (by minimising the write amplification ratio). With two smaller drives you start out with a lower potential to take advantage of this.