RFID Timing is really a cloud, not an accurate line. It is a great tool but it cannot decide close finishes like the Alaska race without support cameras.
The only correct thing to do is like the poster described in Illinois HS State Meet - chip timing, integrated at the finish with high speed cameras. In Illinois they have used the IPICO system integrated with FinishLynx for several years, and get brilliant results. And they give intermediate splits and intermediate team scores live in the park at 1 mile, 11/2 miles and 2 miles.
It is imbecilic to talk about a bib chip being better. It is the same RFID cloud. And wearing the chip on the chest is absolutely not more accurate than wearing it on the foot. In fact it is worse on the chest as there is more interference there than closer to the antenna.
The rule for finishing is the torso, It is stupid to rely solely on chip timing for cross country results. Close finishes need to be decided by a high speed camera. Come and watch the Illinois HS Meet to see how it should be done.