Since 1.5 I've played about 25 hours with no crashes. In fact, with the exception of the slow turns (cpu has the crunch all those factions) the game runs great. It's not perfect, but most of the flaws I see are design issues and not bugs. The AI is still problematic on occasion, but problematic to the benefit of the player. Battles are a little easier than they prob should be, given that the AI is stupid. However, those weaknesses aside in my opinion Empire is the best TW so far. I much prefer how I can manage individual towns within regions in order to combat rebellion, and its fun watching combat up close. Ship combat is a bit weak, but i tend to auto-resolve those.
If you can catch it on sale and have a reasonable machine, I say give Empire a go. Its not the best thing out there, but if you measure what it does right it is overall a great strategy game. At worse, it is to Napoleon TW what Vista was the Windows 7. Ensemble will likely take all the best stuff from Empire as well as a much tweaked version of the game engine (it is very good looking) and make Napoleon what Empire should have been. But Empire is great fun regardless.