You should borrow bitcoins when you have a valid reason and do some research of what kind of loan you are going to use and especially the interest. To be honest it's too risky to borrow or even lend bitcoins here, it's just too risky
Indeed when you need it and you got a good reason to do it it would be worth it but if this is only for the cash I would simply not do it at all because it will than be not worth it.
The most loans requests at this forum are used to gambling and sporting bets, some users do repay early then the period they ask for the repayment. Some people really need the loans and use it to repay for something before they get their payment.