is this coin reasonable save? read about sacam of excahnge and so on...project looks interesting so i am thinking about investiog abit^^ but wont read 500 pages

Definitely. Just think of the potential of feeless payments.
Moreover if Nano can get partnership with a big e-commerce maybe Nano will be very interesting for investment. I think this is our opportunity to accumulate Nano while the price still far from the highest price and seem market start to recover, but better to accumulate little by little so that we can buy again if Nano price going to down
averaging down in buying will help to lock in some good entry and holding NANO should be a safe bet for the future with all the good things in the pipeline
Yeah the best strategy to do right now with the current market is averaging down the price for every cryptocurrency you'll buy, if you look at nano's chart, the price of nano isn't really that volatile, it's quite forming a linear trend which is good, this means that the market is still silent and there isn't really that much volume yet for both buying and selling. This is the perfect buying opportunity because this was basically what nano's chart looks like a couple of months ago before it started skyrocketing. Yeah you're right about that, the devs have a lot of plans for nano and they're now starting to work on fully open-sourcing their technology so that it will be easier for online merchants and exchanges to integrate nano in their platform.
I hope you're right that Nano price could skyrocket again and market condition can be stable because this coin price very cheap and seem a lot of people bought this coin at higher price than now included me. So i think they are now in negative profits if they are not avaraging down the price. But i can't imaginate if Nano team success to fully open-sources their technology, maybe many merchants will interested to using Nano because easy to integration and feeless