One thing to keep in mind when raiding SSD's is that on many controllers TRIM is not supported through the RAID Array logic. Meaning your SSD's slow down over time. Intel has fixed this issue on their own ICH's so that TRIM can work through a RAID0 or RAID1 array but other manufacturers have not been so quick to do the same and it depends on driver support in the OS and requires a firmware update to the motherboard.
Another thing to remember is that many RAID controllers on motherboards are of poor quality with constrained bandwidth and high latency. This can mean that combining two SSD's in RAID0 that would otherwise reach 530MB/s read each may only top out at 800MB/s when combined in RAID0 because the RAID Controller simply isn't strong enough to push both SSD's to their top end performance.
One last thing to consider is the access latency. High bandwidth on sustained transfers is nice but often these common RAID controllers will have insanely high latency compared to when RAID is deactivated and this obliterates SSD's most valuable aspect, extremely low latency access to new data. This is what makes SSD's IOP's so high and I've seen some RAID controllers (Promise, ASMedia and even Intel) which drop an SSD's IOPS from around 90K to 45K-120K when used in RAID0 when it should be 180K (2x90K).
So although RAID may look good on the surface it's not really all it's cracked up to be for SSD use, it has issues with performance degradation over time and you will more than likely take a performance hit straight away unless you have a very good controller, which you obviously won't find on a laptop.
Another thing to remember is that many RAID controllers on motherboards are of poor quality with constrained bandwidth and high latency. This can mean that combining two SSD's in RAID0 that would otherwise reach 530MB/s read each may only top out at 800MB/s when combined in RAID0 because the RAID Controller simply isn't strong enough to push both SSD's to their top end performance.
One last thing to consider is the access latency. High bandwidth on sustained transfers is nice but often these common RAID controllers will have insanely high latency compared to when RAID is deactivated and this obliterates SSD's most valuable aspect, extremely low latency access to new data. This is what makes SSD's IOP's so high and I've seen some RAID controllers (Promise, ASMedia and even Intel) which drop an SSD's IOPS from around 90K to 45K-120K when used in RAID0 when it should be 180K (2x90K).
So although RAID may look good on the surface it's not really all it's cracked up to be for SSD use, it has issues with performance degradation over time and you will more than likely take a performance hit straight away unless you have a very good controller, which you obviously won't find on a laptop.
