It's no longer the 'big dog" having been surpassed by the Corsair performance 3's. The Corsairs are the same thing really as the Crucial's just w/ updated firmware.
The 64 GB models write at 75 Mbps; 128's do 140; and the 256's hit 215.
By comparison, the Vertex 2's write at 275.
So on straight reads (loading stuff), the C300 will do better .... for swap files, temp files and scratch disk usage, the Sandforce jobs are the way to go.