i think the ego-C's main design point was honestly to find a way to get more $. They appear to be the same parts as in an egoT (more or less), but can be separated. magically during the separation process they of course ended up costing more when combined, in comparison to a regular egoT atomizer.
anyway, i love their batteries, but am prefering to go with cartomizers for now. a big dual coil low resistance cartomizer (2x3ohm as 1.5ohm) blew the egoT B amotizer (which is a big improvement over the A atomizer) out of the water in terms of vapor and taste (to me anyway, i guess its all subjective though), they're much cheaper and seem to last just as long.
but either way, you can't really go wrong with an ego anything, as i believe they're all the same battery threads, so you can use the atomizers (A/B/C/W) interchangeably on any single battery. so buy whichever you feel like, and try out the other atomizers seperately if you're curious or want the best opinion of all: yours
one thing i did love about the tank system (never had any leaks on my egoT) was the ability to swap out the tanks/flavors quickly. which was great when i started and had about 15 different tanks filled with different flavors and was trying to find what i liked. now that i know what i like and its basically 3 flavors that i occasionally mix together, i have no need for the swapping around, i just keep 3 big cartomizers filled with what i like and swap out the cartomizer whenever i feel like it instead.
Not sure I'm following you on how they end up costing more than the T? The atomizers are already almost $5 less per atty. Calculate out how many times you'll change out an atty over the time you'd use the unit, and you can see what the savings are. You make a one time investment of $13 for the cone (assuming you don't get the kit), $6 or less (on sale right now) for the atties, and $7 for 5 tanks.
How do you even clean or blow out the atties on the T? I really don't know, since I've never had one, but it looks like you replace the entire cone with the atty inside of it for the T?