I HAVE noticed a overall speed increase with Bryce 5, its not much faster, but it is faster. AS far as the UI goes, thats just a matter of taste. the tree lab is great and for persons who dont own rhino or carara, the metaballs are a great extra. All in All this is Corels first real stab at Bryce and ya have to give them some credit for the advancements they have made on their frst full version release of Bryce. Maybe Bryce 6 will just knock everyone's socks off now that Corel's engineers have a idea of whats going on under the hood, so to speak.