I would not be worrying about this. Whether or not that's the lifecycle of a SSD (which for all intents and purposes is not worth discussing because you'll throw it out first before it craps out) or the read vs write speeds. A hard drive spends more time reading data than writing anyways, so that doesn't surprise me.

But it's all moot. Just buy the biggest SSD you can for the money, and for 99.9% of applications, there will be some other bottleneck worth addressing.