I have a 5 day trip to Japan with NRT-Kyoto-Tokyo-NRT routing with 2.5 days in Kyoto and 2.5 days in Tokyo. We have 2 kids (1 and 3) and 5 adults in the group. Should we just buy JR Pass? Obviously I am going for little extra convenience over slightly lower cost (I am assuming) if bought separately. I am landing in NRT Thursday morning 10:30AM and leaving Tuesday 5.30PM and am staying at Westin Kyoto and Grand Hyatt Tokyo, so I want trains that go to stations closer to them.

myjrpass.com has the 7 day pass for $268 with 1USD-105Y conversion even though the current exchange rate is only around 95Y. Does that mean we will have to pay the difference while exchanging or once you have the exchange order in hand the exchange rate does not matter?

Thanks in Advance.

Edit: I just saw the sticky and started reading it. Sticky appears to have answers to most of my questions, but please feel free to answer them. Thanks