A few days ago I booked BKK-NRT (TG J) and NRT-IAH (NH F) for the first week in March for 86,380 miles. I had bought a tranche of miles with 135% bonus, so those 86.38k miles cost US$1213. The reservation itself had $81 fees/charges. At ~$1300, I'm satisfied with that for a long-haul flight in F.
(Had I bought more miles and qualified for the current 145% bonus, I could have saved about $50.)