Yes, I know that the recommended type of drive for ZIL is always SLC due its superior endurance to writes, however since if ZIL becomes unavailable due failure of the drive or whatever reason it doesn't stop the whole array, and just falls back to the pool, what do others think about using a MLC drive as a ZIL device for certain types of enviroments ?

Reason for that is because MLC drives are obviously much chearper and perform much better in number of IOPS for writes than SLC drives.(Not talking about DDR type drives) Can keep a spare on site or even a hot spare and replace it when it wears out due the many writes without having to take the whole system down and with only temporary degradation on performance.

Just for comparison a Intel X25-E does 3300 IOPS for Random Writes while a new OCZ Agility 3 SATA III does between 50.000 to 80.000 IOPS for 4K Random Writes, or a supported OCZ Talos C Series does 30.000 IOPS and OCZ Vertex 3 does 60.000 IOPS, so even having to replace the MLC drive every in a while might make worthwile use it.

Thanks.