I guess I could say I've "encountered" them... they started shipping about a year ago. I talked to a rep of theirs back in July 2003, when they first announced the chairs, and they were targetting $499 per chair (I guess that didn't work out for them).
Also... I noticed that they are now offering a one-arm "connecting chair." Interesting. When they hit the market, the rep indicated that "yes, you can connect the chairs together, but each chair will have two armrests." I thought that was a bit odd, considering the rest of the market. They apparently had to go rework their design since last year.
One nice thing about them is that they are free-standing. I think the Ambassador Lounger is the only Ambassador that is free-standing. Don't know if that makes a difference for you.
Sorry can't help any more with the build quality question though. Have you called a local dealer? I'd be interested to hear more about them.