Sure, I'll try to resume it.
Normal smoke edition sounds veiled to me, like there's some layer between you and the sound, which I hate.
SPC let's it scale better and removes some of that veil. I feel it has slightly more detail and the mid bass is better, as it dont bleed as much into mids (which I really value). Sound stage is also slighly improved, but I think it's psycoaccousting from treble/detail.
I use it foamless, tho. I prefer clearer signatures and detail to bassy bloated signatures. I really believe VE stuff sounds better without foams or with donuts/non thick foams (Zen is the best example of this), but YMMV.
To be honest, I'd not order any of the two. Just grabed some buds from a box (trying to downsize) and did some very quick comparitions. My picks would be, within my collection:
** Warning: I know nothing about this hobby compared to people like @WoodyLuvr, @RikudouGoku or @furyossa, just to name some. My opinions should be taken with a grain of salt and you should seek opinions like these guy's over mine. I'm a music enthusiast who got into the hobby around April/May and got into the bud world even later. **