From my perspective and if we take that i'm pretty new in all of this, for me is the best too keep and hold on long terms. I start with 10 etherum when it was 16 $ but then someone stell my etherum and i buy a new 10 etherum for price 34 $.
Soo.. i'm learning more and more every daya and i try to undesrtand what all of you talking about, and where this going. For that reason i'm still in some kind of fear to try to sell coinwhenis price high and then buy again when it is low... for that i will keep my ether and some other coin in exchange and i have a bog hope that etherum will reach the price of bitcoin in near future.
Until then... i'm thinking what coin to use : ) ...to try make some money in some small buy and sell exchange :)