When would 15 year mortgage beat at 30 year?

[John Currey]

We just got our offer accepted on a house for 100k  looking at the amortization we would be paying off way more principal on the 15 year. Its a psyment we can afford either way. 

we plan to renovate the home and live in it for about 3 years. Is it worth the higher payment and slightly lower rate to do a 15 year mortgage? 

right now I'm just going off of what Google says for rates which varies from 5.7% to 7.3% for 15 year loans. Does any know the most like interest rate for 100k with 3% down and 760 credit all the websites are giving me different answers.