Cold ethanol extract. Recommendations?

[jascan]

After reading the "Cold Ethanol Extract" thread I am ready to start on my own. Any recommendations on the best type of tobacco to use? That would likely leave me with the least "gunk" and most alkaloid content. I will be ordering an untreated, unprocessed, as "raw" as possible whole leaf tobacco. Any recommendations/advice would be greatly appreciated. Thanks in advance!