I'll chime in and say I like my Therion 166 quite a bit. Excellent build quality, feels great in hand, it just comes across to me as being very solid. I'll preface it by saying I only vape in TC and like the customization the mod lets me do (I'm going to post my Ecig file soon).
However I don't have the Smok so I can't compare the two mods. I was just chiming into to say since I've received the Therion, I haven't put it down. I think the Black Frame looks sharp as well (personal preference). It really comes down to what you like the best and think will best suit your wants and needs.
Cheers,
Steve