The 128GB m4 is just superb, I like it a lot.

Here's an AS SSD comparison of my m4's.

forgot: 256GB to the left and 128GB to the right.

as_ssd_mbps_128vs256.JPG
as_ssd_iops_128vs256.JPG

Cant speak for the 120GB SF drives but the V3 240GB is just marvellous