I would not waste money upgrading from one budget device to the next. Really in perspective, as someone whose owned all over the budget spectrum
(Behringer, Yamaha, Mackie Onyx, EMU, M-Audio, I've also used the firepod extensiveley) the differences aren't that big. Yes their are slight noticable difference, but when comparing it too having one professional preamp, their are no differences between an Onyx and a Yamaha MG mixer preamp. In your case the main reason to go firestudio, I would think do you want the Digital I/O for a possible upgrade path to higher convertors, and monitoring control. Otherwise stick with the firepod. and Put the 200$ saved else where.
Also the focusrite Sapphire pre's are derivitives of the Green pre's used currently on the twin track pro, Voice master Pro, and Octopre. I do not think the circiut is the same but very similiar. I've heard of some driver issues with this, so I'd be wary there, especially for windows users.
"Will using Logic and Reason make me look smarter?"