I've spent £100s on both Imagine and LightWave. For me, the ease of use and the sheer power of LightWave make it the best 3D application on the platform. I dabbled with an early Real3D coverdisk, but didn't like it much. And Imagine was very cumbersome, with six different interfaces if I remember right. However, Imagine was the one that got me into the whole 3D thing. The coverdisk started it and I was hooked. LightWave cost ten times the price of Imagine at the time, so it was out of reach. Much later, I managed to get one second hand complete with the dongle. Imagine was immediately forgotten. In my opinion LightWave 5 on the Amiga is for more useable than Imagine will ever be. I also think Imagine produces less 'natural' looking renders. I could always tell an Imagine render in the mags, but LightWave images can be truely photorealistic. Depends on what you do with them I guess.
JaX