I just replaced my original, constantly clicking, HDD drive with this Active Media Products 64GB 1.8-inch PATA ZIF SSD in my Macbook Air (1st generation) a few days ago and am happy with the results. Now I have a lithe, quiet-running, durable mobile laptop. The manufacturer claim 80MB/sec Read, 38MB/sec Write speeds for sequential memory access which is well above the benchmarks found in 3rd party tests on Apples original SSD drive of up to 49MB/sec Read and 9MB/sec Write speeds:
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I am not able to verify the alleged improvement over the original SSD, however, I perceive an all around faster performance over my replaced HDD. Of course you will need to install the SSD drive yourself--a process that will take the patience and nerve of a brain surgeon, as the guts of the MBA are packed dainty and tight. See Fixit's "Macbook Air Hard Drive Replacement" instructions (hard to find but they are there). Also, note that as far as I know, this drive will only replace the drives in the first generation Macbook Air.