What is the one atty, tank, add on, accessory, whatever that you feel is the cherry on top of your ego? I need help making my next order! 
I tried a mega dual coil the other day. Had a permanent burnt taste from the first hit. Did I just get a dud or something?
Possibly. Is there a dual coil option without filler? Not a fan of it.
Ego Mega Dual Coil Cartos. I actually haven't put much else on my eGos since they came out 6 or so weeks ago.
EMDCC cartomizers.
For me, it would definitely be the Ego Mega Dual Coil Cartomizer. If you fill it correctly, it holds over 4 ml of juice on the first fill and gives outstanding flavor, vapor, and longevity. If it doesn't blow you away, you've either done something wrong or you have one of the rare duds. They're $2.49 each and go for weeks. Here's a link to limit confusion:
eGo Mega Dual Coil Cartomizer
Ok, EMDCCs win. What's the correct filling method for these? It seemed like every drop I added after the filler was soaked ran right out the bottom.
Well then I guess I had it right the first time. Guess I'll just toss this one and hope the next one tastes better.
I've had one taste pretty nasty for the first couple hours - there's another post around here somewhere about someone finding black primer oil in the thing but that appears to be pretty uncommon - this other poster and I are the only two I've heard mention it.