Which is the fastest way to plot several 2D contours on one 3D plot?

I need to plot several 2D rectangle contours on one 3D plot like this:

To plot these contours I have more than 200000 dots with corresponding X, Y, Z coordinates and vector V with results of my calculations. The color is based on value from V, not on the level of the dot (for this I created a custom non-even colormap). I didn't find a normal way to plot my results, so I did it by cycling fill3() to plot rectangles nearly 50000 times. Even this cost me 70 seconds of plot time, 65GB RAM and wild lags. 20 cores on my workstation didn't help. I succeded in saving the figure, but couldn't rotate or move it.

Can you suggest me another way to solve my problem?