If u r sure that u can get the 1st,u c*ways do it as more dmg gets you more exp & coins.

1st place get 60 coupons. So minus away the 30 coupons you will still get 30.

If you r thinking of the ROI (return of investment) it is worth it.

But if we think it in another angle, spending 30 coupons with the risk of having to gain 5 more coupons/exp/coins .