[QUOTE=yojimbo;17995272]When using miles, I generally try to get $.02 in value per mile, vs. the price in $$ I would otherwise have to pay for the ticket.

e.g., faced with a choice of paying less than $500 for a ticket or using 25,000 miles, I will usually pay cash.

Well put, $.02 is a good rule of thumb. I wouldn't go less than $.015 and anything over $.02 is very good. Fuel and other charges also have to be figured into it.