So far, I have booked four one-way flights using Lifemiles, instead of two return journeys. All points have been purchased during 2:1 promotions and the following are the flights I booked. Values (points and US$) are for two and hopefully are interesting as reference points:
SYD-BKK-ZUR, booked March 2013, flights in August, F on TG. Can't find confirmation email right now but we again used 40% points plus co-payment
TOS-OSL-FRA-SIN, booked March 2013, flights in September, J including SQ A380. 52K points + $1,154.14
SYD-BKK, booked April 2013, flights in December, J on TG. 86K points + $462.35
VTE-BKK-SYD, booked April 2013, flights in January 2014, J on TG. 38K points + $882.72.
Everything went well with the exception of the return journey from Europe, which will be coming up next week. No flights to Sydney were displayed so we decided to book the flight to Singapore only, and use QF points to get back to Sydney. Very happy about the A380 redemption, and the J flights to Thailand/ Laos for our Christmas break were excellent value.