I didn't have an graphics card so that was probably the main reason it was so slow for me. I played with it a little but it loaded so slow and everthing that I didn't use it to much. As far as bugs go I didn't really find any but like I said I didn't play with it much. Is seemed very stable but without a graphics card and my lack of memory it was hard to really use. The rendering did seem faster than Bryce and a lot cleaner. I would get more memory, especialy since it's so inexpensive right now, and go for it. It really is a awesome app if I can ever figure out how to use it. :)