I used Man for lumber options, and they were terrible (I mean, they handled the lumber market fine, but Man as a whole is terrible). I'd echo some of the previous comments on the liquidity of the lumber options market. If you're trading ATM options, you can expect reasonably quick (and not terrible) fills. If you're trading anything more than 2 strikes out of the money (or anything not front month), be prepared to wait *days* unless you want to give up huge amounts of IV. I wasn't doing more than 10 contracts at the time, so that may have something to do with it.