What is in your opinion the best altcoin to invest in for 2016 and why. Pls add why folks.

I'm still in Primecoin XPM, CryptoBullion CBX, and Horizon HZ for longterm. Those have solid reputation and a good base for growth.
*** I do not recommend to invest in any mentioned coins without proper research, how it was launched, how it developed, community involvement, stamina, price history and volume, etc. So do your homework cause you're the only one responsible for your funds.
I think for 2016 XEM is good alt coin to invest, but it is your duty to study how does this Alt coin grows and how XEM run. in my own opinion and research Xem is a good alt coin to invest. NEM will soon launching the XEM wallet app. try to study and research more. and you and only you can answer where so you like to put your funds to gamble.