You didn't say if your got the 100K from Chase CSR or other cards. If you got it from CSR, you could also look into using the UR points to buy tickets thru the UR portal. A quick check shows plenty of under $800 roundtrip tickets from LAX to NRT in November. If your have CSR, your 100K UR point is $1500. It could cost you less than transferring to airline + buy miles + fuel surcharge.