If you are not bothered about collecting air-miles that BOOK with flyl4l... Simple!
Judging from
this post, this company seems to be a mileage broker.
I understand you had a wonderful first encounter with them, but with due respect, I am not that sure nor comfortable dealing with any mileage broker myself.
You are basically buying miles from another "seller" through this broker (i.e. 3rd party), which I have no idea if they establish any partner relationship with named airlines. Not to mention selling miles is in violation of most airline's FFPs that I know. OTOH, Points.com has their business model/relationship with a number of airlines but I rather not conduct any trade with Points (bad value, high fees...etc).
Here are two sample threads about selling miles and implications over
MilesBuzz! Forum for your reading pleasure:
http://www.flyertalk.com/forum/miles...ell-miles.html
http://www.flyertalk.com/forum/miles...-com-scam.html