You may want to consider the ECHO E cartomizers...they work with the ego batteries...cost about $ 5 ...getting good reviews...no leaking
Well I bought an Echo E carto as you suggested and I have been using it for the last couple of days with my Ego batteries.
It fits perfectly and makes the juices taste 10x better than the tank ever did.
But most importantly, no leaks at all and no juice in the mouth!
It safely holds 3ml of juice and none of it leaks out as long as you lean the carto to one side and drip the juice SLOWLY down the inside wall while rotating it and without getting any into the centre hole.
With a new atty on the Ego T it was a case of fill the tank, burnt, burnt, burnt, burnt, burnt, flavour, flavour, blocked, leaking, huuuurgh there's juice in my mouth.
With this its more like fill the carto, flavour, flavour, flavour, flavour, flavour, flavour, no flavour...time to refill, flavour, flavour, etc
A nice suggestion sir, thank you very much!
Also, I bought this from Genesis in the UK and while I was at it I bought a couple of bottles of Genesis juice, which coincidentally taste a lot better than the TW juices I have been using lately. When I first got the Echo, I did try it with TW juice though otherwise the comparison would not have been fair.