I'm on the e-lites too! Three months now and I did use patches to start off with as well.
I get a bit annoyed with myself at times as I know I have swapped one habit for another but hey....
Craft, I used to smoke about 30-40 a day and I use a cartridge every 2-3 days now, I think that works out at about 70 p a day.
I've had a couple of issues with thingys breaking but the customer services are great and will send out replacements by return post.
As for leaking cartridges....as long as you stop using it as it begins to slow down it shouldn't happen. Lol, does take a bit of practise though....nothing worse than trying to get that last puff to be rewarded by a mouth full of that sweet yuck!
Lisa x
http://www.e-lites.co.uk/ if you want a further look