I'm not now but have in the past. During the evening (last time I looked) it is pretty thin. During the morning hours NY time it's probably deep enough for small lot trades.
Why don't you look at the Time & Sales? There's often 100+ lots going off - so how much do you want to trade at one go? If you are going to trade anything on a reasonable scale you need to be able to answer questions about liquidity for yourself.
