Sometimes you have to make these sorts of decisions on the spot, so it helps to be very good at math, though just being comfortable with numbers is usually enough. (travelcodex.com)
While it is easy to get yourself excited, I usually try to avoid making impulse decision on the spot. (bassinetandcrib.com)
I had to speed read them on site and make a quick decision on the spot. (thebatavian.com)