If you are looking for a long term hold and do not want to worry about watching everyday if it drops to nothing then I recommend MVTG.
One of my Favorite pick for low maintenance but looking for Real Potential in Green energy with Partners who are Huge in the billions...
I suggest check out their partners and see what kind of credential they have... This will be the next Power PLUG or better as their product is superior in everyday Fuel Cell but Revolutionary in every way and Multiple patents to protect their Technology Please to start look at their partners: http://mantraenergy.com/partners/
Mantra Venture is what the WORLD need with Rapid Climate change and if you see it's more like a Science Fiction type technology and very complicated but I know they will be huge as this will show to the world energy leader what this technology is about....
Also check out Alston as they just agreed to fund over $300,000 here is some info from wikipedia
They are OTCBQ and SEC registered for 8 years!!! and currently have a Project with Mantra MVTG pretty big and Research and Development for 8 years now and if the look at the chart this is the only OTCQB which is in the highest tier with a uphill chart... Not a pump and dump...
The time for Renewable Energy is NOW Ask Warren Buffet what he putting his money on which sectors and he will tell you the same...
Please do your DD before you make any purchase as I always recommend take a grain of salt from other poster but trust your own DD...