I was toying with the MVP3 or the eLeaf 50W. I'd already had the MVP2 and while I liked it, it's battery life was really rather poor. What I mean is that I bought it in Jan 2014, and by Jan 2015 the battery would last about 10 or 20 puffs of a simple nautilus tank at 1.2Ohm. So I didn't want to buy another one thinking that might simply be their battery lifespan.
I went with an eLeaf 50w (as did my partner), mine has been flawless (so far, keeping my fingers crossed), where as his used to autofire if he was holding it at a certain angle to vape, then when he let off the trigger it would continue to fire. He took it back to the shop and they opened it up and cleaned it out and told him that they found "dust" inside of it, I'm going to take the stretch and assume they found metal flake dust from the mfg process and cleaned that out. It's been fine now for a few weeks since they did that.
I imagine that there will always be defective units that roll off the assembly line but out of the thousands, tens of thousands, hundreds of thousands of units produced the number of complaints seems relatively small to me. Still, it sucks to be that person that wakes up in the middle of the night by the smoke alarm in ones home to find that the rag your mod was sitting on being charged has burst into flames and lit up the kitchen curtains etc.
But beside the short battery life of my MVP2, I really just like the way the eLeaf fits in my hand, it's just so much more comfortable and feels a lot smaller.
Knowing what I know about the defects that have been found in it, I'd still take the chance and buy another one if I didn't already have one.