MOTM

>So what do you folks use for VC panning?

I built my own dual VCAs with enough controls on them so that I can 
easily do VC panning without having to tie up a bunch of other 
modules. I have an initial gain knob, a linear VC input (with 
reversing attenutator), and an exponential VC input (also with 
reversing attenuator).

http://www.tellun.com/motm/diy/tln132/TLN-132.html

I can easily set these up to pan with linear or exponential voltage 
sources that are +/- 5Vpp or 0-5V. I believe the MOTM-130 (RIP?) will 
also have the necessary features for auto-panning.

I find the smoothest panning uses sine waves (rather than triangle 
waves). But I also like to use various Miniwave waveforms for really 
bizarre panning. See the above link for some VC panning samples with 
sine waves and linear vs. exponential response.