Avianca LifeMiles is running 100% bonus promotions for buying LifeMiles almost every month now. For Cyber Monday, the company has actually put out a special offer that is only valid today!
The bonus amount is now 125% – the highest bonus I have ever seeing for buying miles.
This brings down the price of miles to about 1.5 cents (there is a fixed $33 transaction fee).
I recently redeemed all my LifeMiles and have no interest in buying, but LifeMiles are great value for close-in, short-haul flights in Peru and Colombia. If you need flights from the coast up in the hills, it's a good currency (but so is Avios).
Keep in mind that airlines basically just 'print money' when selling miles. So every mile we buy contributes to the bottom line of an airline. It seems LifeMiles really makes a decent amount of money with every transaction we send there.