IT is verry useful to borrow bitcoins right now because the price of the bitcoin is great to buy them now because i know for sure
That the price of the bitcoin will rise allot at the end of this year so if you want to borrow some do it Now.
I am sure you know nothing.. 650$ is not great price to buy bitcoin. the right time for borrow bitcoin was 3 months ago when bitcoin price what under 400$.
now it is very expensive and you can't even know that if you borrow bitcoin today, then will you get profit or not? or may be bitcoin price drop again at the halving... everything can be possible,
although chance of its price increase is high but if I were in your place I will never borrow bitcoin at this price. now it is your call to take risk or not..