i am using a small samsung xp941 as boot drive. the current ones in the market need heat sink to help dissipate heat. for cost reasons, i think 2x 256gb sata ssd raid0 can achieve better performance.

worth it or not, yes to me it's worth it. however, if possible, you should wait for models from other brands (with speed higher than 1GB/s).
yes, these benchmarks apply to the same ssd in Malaysia.

as for firmware fix, you can check out the manufacturer site for the latest, and apply it yourself via intel ssd toolbox software.