Carrara is definately a great program. It does lack a few really basic things like being able to rotate a projected texture or HDRI map about an arbitary axis, but as a whole is great for the price. HDRI/GI are really fast. I am using an athlon 850MHz and I often leave GI on with anti-aliasing even when I am doing test renders. I do have some problems with area lights producing aritifacts on anything but the best light quality settings. I have had the odd crash now and then but nothing where I lost my work as I was still able to save and restart the program once the error had occured. There are a few bugs here and there but there is nothing that has really impared my enjoyment of the software. I am really looking forward to version 4 as the quality of this product seems to be increasing exponentially. It should be excellent. One concern for me is that they will never really beef up the modeller as it would start to compete with Amapi which if is true is a bit of a shame but we will just have to wait and see.