I've been using a redbox for about 10 years and swear by it. but it kinda depends on what you use it for. It's not so much an amp simulator as a cabinet simulator. I use it on older pedals and multi-effects units when I'm recording direct. It smooths out the top end cheezy fuzz sound so it sounds more like it's coming through a speaker cabinet.
However, if I'm going to be using something like Amplitube later, I'll use the direct signal cause it's more accurate.