Oh dear, I see that patience isn't always employed by some. This is the first time I've seen this post and to be honest, a rabbit forum isn't the best place to be asking about carboard substrate as most people use hay so 2 hours for a response in the middle of the day really isn't leaving it that long.
In answer to your question I think that Finacard is very good. I use it for my rats. It's very absorbant and keeps smells down. I personally wouldn't use it for rabbits as I find hay and newspaper more than adequate and would go through quite a lot of as my rabbits have a large litter tray that gets changed daily.