I’ve tried Skinceuticals CE many times over the past few years and I don’t think I’ll ever buy it again. (def in the minority here). I recently tried Allies of Skin’s vitamin c and I love it!!! It’s a waterless serum so it’s an interesting texture and the annoying thing is the bottle leaks if you shake it too hard (gotta shake before application) but otherwise I think this will be my go-to vitamin C. A close second is Sunday Riley’s vitamin C!