just a reminder to those planning to get secondhand SSD. Note that all SSDs have limited lifespan. Especially those made with MLC chips. Those more expensive using SLC will last a lot longer but price very very high.

So I can say nearly all are made using MLC which some said have 3000-5000 writes only. Whatever it is, just don't pay too high for secondhand SSDs.

Take note also TRIM is very important to make the drive last longer and long term performance.

Most ppl use their ssd to run the os. This means there will be lots of write operations. Logging, virtual mem, caching, temp files....

I don't know how the empty blocks are written in SSDs. Whether they are taking turns for each block (somewhat intelligent method) or the OS just write to whichever first block that is available. So in theory based on the second method (which is used by most HDD) a certain cell could be overwritten more than another. So much so that this block will fail first. Means once that block failes, the whole SSD is useless already.

Anyway, in theory....manufacturers will bloat up their product lifespan. I think modern SSDs should have no problem lasting 3 years. However, beyond that you will be going into a territory where you are sure the hdd will fail soon. Compared to magnetic HDD, the failure rate after 3 years is not as "a sure thing" as SSDs.

I would say just get any SSD based on your budget. If you have enough budget then get those super high performance SSD. Else just get a basic SSD will also be good enough. A basic SSD is already very much faster than old fashion HDD. FYI, those super fast SSD is not really the much faster. Only in benchmark you can see them really fast but in real life, it is not really noticeable. Just like GPU benchmarks.

I have an Intel 330 40gb SSD (running sataII only). The boot up into windows 7 take only around 15 secs. With super fast SSD, this might become 12 secs. But with old HDD, that's around 3 minutes (180 secs).