Buy.com offers the Crucial 512GB M4 2.5" Serial ATA 6Gb/s Internal SSD Solid State Drive, model no. CT512M4SSD2, for $396.49 with free shipping ($0.77/GB). That's $134 under our April mention and the lowest total price we've seen for this SSD. (It's also a current price low by $24.) It features read speeds of up to 415MB/s and write speeds of up to 260MB/s.