I think quality wise it should be about the same, Filco SA are made by Signature Plastic.
As for sculpted SA, I think it's entire based on preference.
For reference, I hated sculpted SA while other people raved them. My ideal is all row 3 SA, even Filco's row 2 bugged me (I own a set too).
So if you enjoy it then I'd not worry about it. But if you're curious then maybe you should get a set from Maxkeys since they're quite a bit cheaper than the SA sets.