Had the Melo 300 about a week. I use Naked 100 #LavaFlow it is a 70vg with 3mg of nice. Has great flavor, huge cloud, and I run my JayBo Wisemec 300 mod on 120 watts. Hands down the best tank and mod combination to create huge cap and great flavor.

Haven't had any problems leaking!
As far as getting hot if I continue to constantly hit it it will get warm.

Coil life....remember to use a push pin and poke 2 holes in the cotten on the side holes on your coils. Helps with priming and it won't burn your coil when you get low on juice.

Gets super hot, aND leaks through the air inlet constantly. It's brand new. I'm only using like 35 watts and it get uber hot after like 5 pulls. Can't imagine at 300w. The leak is the most annoying.

I am having a problem getting one of theese apart to change the coil. I love these on my Pico and i-Stick. Too hot? Turn dowm the wattage or add air! I love that these are top-fill. Most of the juice I use I have mixed, myself. I do use tobacco flavors some times. The only proble I had was with my pink lemonade. The tank started leaking. It was easy, surprisingly, to take apart, clean, and change the coil. I added my other fave juice, no problems! No, I did not change the plastic rings! Personally, I love these tanks! Ymmv

I have every smok tank they make. Biggest complaint with smok is their coils they simply don't last. Flavor falls off in two days and day four it's done. Sometimes it doesn't even last four days. The melo 300 coils last twice as long and better flavor. Does take half a tank to set the coils in so a funny taste at first on a new coil. The filling is great! Nice positive closed and open detents. Smok I either get a super losses fill lid or super tight. Nothing like one popping open in your pocket. Quality just fees better to. Imagine they have tighter tolerances than smok

Like others have stated, this tank does give incredible flavor - but after just a few rips at 74 watts, using Eleafs own iKonn 220W TC Vape MOD, it gets HOT. I knocked it down to 68, then 60 - still gets really hot after only two or three rips.

So while this tank is HUGE, and the flavor is great - why would anyone buy this tank? You can only rip it three times max before it's too hot to use.

Which is aggravating, as I was trying to replace my leaking Big Baby Beast, Baby Beast, and Cloud Beast. I have had ZERO luck with SMOK products, and figured I'd give this Eleaf a try.

Personally, I'm moving on. There HAS to be a tank out there that won't leak, gives good flavor, and doesn't get HOT! :)

Predator 228 has enough watts but not enough volts to power this tank. Tank gets hot. Uses alot of power and juice.

I'm using a smok alien 220w tc with this this tank and at 100 watts it gets way to hot. You get what you pay for. In my opinion its bad. Huge tank suppose to be 6.5ml but it's only 5ml I tested it. You have to use a lot of juice just to prime it. In less someone knows a trick I don't know it's garbage. My aspire cleito make bigger clouds saves juice and doesn't get hot.

Recently we tested Eleaf Melo 300. If you are looking for a "super tank" for a cheap money, Melo 300 is just in time. You will get massive amount of clouds and flavor will not stay behind :)
You can also find a deeper review here http://ecigopedia.com/eleaf-melo-300-review/