I've taken a look at the FF award booking engines on the AA, BA, UA, NW, and QF Web sites, and my favorite award booking site surprisingly belongs to:

British Airways
Pros
- 5K mile discount on transatlantic bookings before 12/31/02
- Able to book tix to any BA destination
- Able to book stopovers (if on direct routing)
- Able to see award availability for an entire month at the same time


Northwest Airlines is my second favorite site
Pros
- 5K miles award booking discount on international tix
- Able to book domestic and international destinations
- Able to book KLM code share flights

American Airlines operates my least favorite award booking site
Cons
- only domestic tix
- only PlanAAhead 25K coach awards

Are there any better/worse airline FF award booking sites?

I have experience with LH, AA and KL.

My favoured is LH. Fast, efficient. You can book most international tickets without stops. You need to call them when you want to make a stop or when you need an airline combination (like UA domestic and then LH international, as long as the UA flight does not also come with an LH flight number).

Second is KL. Also no stops. Also because of their strange married segement rules often no availability for connections when both legs are available.

AA is distant last.

I skip the whole mess of trying to work with the airlines' sites. I use AwardPlanner.com (that blue box that is often at the top and bottom of the FlyerTalk screens).

For $45 a year, AP takes all the work out of the job of getting award tickets.

I use Worldperks on the NWA.Com website.

It usually works fine if I book the award tickets early enough.

Good Luck!