Here's another way to calculate for the penny pinchers out there. If Scarlet doesn't come with SSD. You'd spend $2400 to get the module and a 64gb SSD. Four 16gb Red CF cards would cost you half that. If you're willing to "risk" using third party CF cards, the Lexar 32gb 600x cards on Amazon go for $232, and the SanDisk 64gb 600x for $400. Cutting the price from the SSD to a sixth.
Though I'm sure Red will tell you flat out if you use these 3rd party cards there is no guarantee they will even work, and if you end up with dropped frames, audio or other compatibility issues while on set or in post, don't come crying to them.