As it turns out and I didn't expect this:
Both columns have nearly identical output rates. Some time ago while working on the VM column I got a PM from Riku indicating I was at the limit for pure product on 3" column by calculating vapor speed in the column. That theory is apparently correct because I was not able to collect at 95.6% when I increased the takeoff rate past the gallon an hour on the Bok.
The VM column will not exceed one gallon per hour. When I add more heat the reflux ratio increases but output remains stable. The VM column I built is in this thread http://homedistiller.org/forum/viewtopi ... =17&t=7647
The Bok because it's condensing all the vapor can be driven to higher output rates but I found an immediate decrease in quality as soon as the takeoff rate went over the gallon per hour. It was really uncanny. I suspect the Bok might squeeze a little more if the column had been fully packed but I did not want to do that as I was 'stilling white rum.
So now having experience with both VM and LM columns of the same size and length my conclusion.
For ease of operation the VM column wins hands down. It's nearly impossible to make a mistake with that column. On my last run after heads had been removed I opened the ball valve wide open and collected for just over two hours, one gallon per hour of pure 95.6. On the first indication of temperature increase I closed the valve down to reduce output and collected 3 quarts of 95.6 over the next two hours. At that point the still had slowed to a drop per second and I shut down.
The Bok was rock solid stable for two hours as I collected the first two gallons. Although it wasn't difficult the takeoff rate required several adjustments through the next two hours to keep it at 95.6% with max output. I was able to collect another 2.5 quarts in that two hours. It certainly was not difficult but not nearly as easy as the VM column. In my opinion the VM build is a bit easier with off the shelf parts. The Bok requires a bit of skill in layout and patience in cutting and soldering the still head but the design is definitely elegant and perfectly balanced. The cooling liebig only needs to be very tiny also a plus.
Either design will get you a great product. If you need to drive the still to lower than 95.6 you'd be better with the Bok.
Hope this helps some of you folks trying to decide which way to go...............
Jealous! 
Outstanding report 
Guess you folks have figured out by now I hate unanswered questions and besides I had most of the sugar. I also had 3 packs of Alcotec Vodka Star turbo yeast which I didn't like. (too slow) so I pitched it all into one 60 liter ferment and the other ferment I used bulk bakers yeast, dap, and lemon juice. I threw in the aquarium heaters and they're bubblin' away. Both ferments have 14KG of sugar for 14% potential. I know the turbo will work right down to .990 but I'm wondering 'bout the bakers yeast. I expect these ferments to go a little slow because the heaters only work at the top of the wash and the bottom is quite cool.
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